Chevrolet 70 Series 1970 Service Manual Download

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BRAKES 5-36

O n c o n v e n t i o n a l m o d e l s a n d S e r i e s 9 5 0 2 m o d e l s

t h e

c h e c k

v a l v e

i s

b u i l t i n t o t h e a i r t a n k a t t h e

p o i n t w h e r e t h e t a n k i s d i v i d e d ( s e e f i g . 1 1 ) . T h i s

t y p e

c h e c k

v a l v e

i s

s p r i n g - l o a d e d

v a l v e

a n d

f u n c t i o n s

t h e

s a m e

a s

t h e o t h e r o n e - w a y c h e c k

v a l v e .

T h e

v a l v e

i s a c c e s s i b l e b y r e m o v i n g t h e

v a l v e c a p f r o m

t h e a i r t a n k . U s e c a u t i o n w h e n r e

m o v i n g c a p a s v a l v e i s s p r i n g - l o a d e d . R e p l a c e a n y

p a r t s w h i c h a p p e a r c o r r o d e d o r d e t e r i o r a t e d .

D I V I D E D T A N K C H E C K V A L V E S E R V I C E

( R e f e r t o F i g . 1 2 )

1 . D r a i n a i r f r o m

a l l r e s e r v o i r s .

2 . R e m o v e c a p n u t c a r e f u l l y . N u t c o m p r e s s e s

v a l v e s p r i n g a n d p a r t s w

i l l " f l y o f f " i f n o t r e m o v e d

c a r e f u l l y .

3 . R e m o v e

s p r i n g ,

s p r i n g

s e a t ,

a n d

v a l v e .

4 . I n s p e c t a l l p a r t s f o r c r a c k i n g , d e t e r i o r a t i o n ,

o r s w o l l e n c o n d i t i o n . D i s c a r d a n y b a d p a r t s .

5 . C l e a n v a l v e s e a t a r e a .

. R e a s s e m b l e , u s i n g n e w p a r t s a s n e c e s s a r y .

I n s t a l l v a l v e , s p r i n g s e a t , a n d s p r i n g .

7 . C o m p r e s s s p r i n g b y p u s h i n g d o w n o n c a p

n u t a n d t h r e a d c a p n u t i n t o t a n k . T i g h t e n c a p n u t .

. B u i l d u p a i r p r e s s u r e i n s y s t e m a n d d e t e r

m i n e e f f e c t i v e n e s s o f c h e c k v a l v e b y o p e n i n g d r a i n

c o c k o n " w e t " p o r t i o n o f t a n k a n d n o t e p r e s s u r e

r e t e n t i o n i n " d r y " p o r t i o n o f t a n k .

SAFETY VALVE

A s a f e t y v a l v e i s i n s t a l l e d i n a i r t a n k t o e l i m

i n a t e t h e p o s s i b i l i t y o f a i r p r e s s u r e b u i l d i n g u p i n

t h e s y s t e m b e y o n d a s a f e m a x i m u m i n t h e e v e n t

o f f a i l u r e o f t h e a i r c o m p r e s s o r g o v e r n o r .

O P E R A T I O N

W h e n p r e s s u r e i n a i r t a n k i s b u i l t u p t o e x

c e e d 1 4 5 t o 1 5 5 p s i , a i r p r e s s u r e f o r c e s b a l l v a l v e

o f f s e a t , p e r m

i t t i n g a i r p r e s s u r e t o e s c a p e t h r o u g h

e x h a u s t p o r t t o a t m o s p h e r e . A f t e r p r e s s u r e b l e e d s

d o w n , s p r i n g f o r c e s b a l l b a c k o n t o s e a t .

M A I N T E N A N C E

C h e c k

s a f e t y v a l v e p e r i o d i c a l l y f o r l e a k a g e ,

Body

Ball Seat

Ball Valve

Exhaust Port

Spring_______

9 5

6 Adjusting Screw
7 Stem

8 Lock Nut

9 Spring Cage

Figure 13—Safety Valve

u s i n g

s o a p s u d s a t e x h a u s t p o r t , w i t h 9 0 p o u n d s

p r e s s u r e

i n

t a n k .

L e a k a g e

s h o u l d

n o t e x c e e d a

3 - i n c h

b u b b l e i n 3 s e c o n d s . O n c e a y e a r , s a f e t y

v a l v e s h o u l d b e d i s a s s e m b l e d , c l e a n e d w i t h k e r o

s e n e ,

a n d r e s e t t o b l o w o f f a t 1 4 5 t o 1 5 5 p o u n d s

p r e s s u r e .

A D J U S T M E N T ( F i g . 1 3 )

1 .

L o o s e n l o c k n u t .

2 . A d j u s t p r e s s u r e b y t u r n i n g a d j u s t i n g s c r e w .

T u r n c l o c k w i s e t o i n c r e a s e p r e s s u r e o r c o u n t e r

c l o c k w i s e t o d e c r e a s e p r e s s u r e .

3 .

T i g h t e n l o c k n u t .

RELAY VALVE

R e l a y v a l v e ( f i g .

1 0 )

i s u s e d a t r e a r b r a k e s

o n

a l l

t a n d e m

a x l e

m o d e l s .

R e a r b r a k e a p p l i

c a t i o n

a n d

r e l e a s e

i s

m a d e

t h r o u g h

t h e

r e l a y

v a l v e .

T h e

s u p p l y

l i n e

f r o m

t h e a i r t a n k c o n

n e c t s t o t h e c a v i t y i n t h e l o w e r p a r t o f t h e v a l v e ,

p r o v i d i n g a s o u r c e o f h i g h p r e s s u r e a i r c l o s e t o

t h e r e a r b r a k e c h a m b e r s a t a l l t i m e s . T h e r e l a y

v a l v e a n d b r a k e a p p l i c a t i o n v a l v e a r e i n t e r c o n n e c

t e d b y a s m

a l l e r a i r . l i n e w h i c h d e l i v e r s a i r p r e s

s u r e

t o

t h e t o p o f t h e r e l a y v a l v e d i a p h r a g m o r

p i s t o n t o a c t u a t e t h e v a l v e . I n a d d i t i o n t o p r o v i d i n g

m o r e

r a p i d

a p p l i c a t i o n

o f

t h e

r e a r b r a k e s , t h e

r e l a y

v a l v e

a l s o

f u l f u l l s t h e f u n c t i o n o f a q u i c k

r e l e a s e

v a l v e ,

p e r m

i t t i n g

r a p i d

r e l e a s e

o f

a i r

p r e s s u r e f r o m

t h e r e a r b r a k e c h a m b e r s .

T h e p i s t o n t y p e v a l v e i s u s e d o n c o n v e n t i o n a l

m o d e l s a n d A l u m . T i l t m o d e l s a n d t h e d i a p h r a g m

t y p e

i s

u s e d o n s t e e l t i l t c a b m o d e l s a n d R 7 5 0 0

m o d e l s . T h e p r i n c i p l e o f o p e r a t i o n o f b o t h v a l v e s

i s

t h e

s a m e .

T e s t s p r o c e d u r e s a n d r e p l a c e m e n t

p r o c e d u r e s a l s o a p p l y t o b o t h t y p e v a l v e s .

R E L A Y V A L V E S E R V I C E A B I L I T Y T E S T S

1 . O p e r a t i n g T e s t

i t h a i r s y s t e m f u l l y c h a r g e d , a p p l y b r a k e s

a n d m a k e s u r e r e a r b r a k e s a p p l y p r o m p t l y . R e

l e a s e b r a k e s a n d m a k e s u r e p r e s s u r e i s q u i c k l y

e x h a u s t e d f r o m

t h e e x h a u s t p o r t o f t h e r e l a y v a l v e .

I f

e x h a u s t i s s l o w ,

c l e a n e x h a u s t p o r t f i l t e r a n d

s t r a i n e r p l a t e s .

2 .

L e a k a g e T e s t s

a . W

i t h b r a k e s r e l e a s e d , c o v e r e x h a u s t p o r t

w i t h

s o a p

s u d s a n d c h e c k f o r l e a k s .

L e a k a g e i s

c a u s e d b y s u p p l y v a l v e n o t s e a t i n g p r o p e r l y .

b . W

i t h

b r a k e s

a p p l i e d ,

c o v e r

e x h a u s t p o r t

w i t h

s o a p

s u d s a n d c h e c k f o r l e a k s . L e a k a g e i s

c a u s e d b y d e f e c t i v e d i a p h r a g m , p i s t o n O - r i n g , o r

s e a t .

c . I f l e a k a g e i s e x c e s s i v e , r e m o v e r e l a y v a l v e

a n d r e p a i r o r r e p l a c e w i t h n e w v a l v e .

CHEVROLET SERIES 70-90 HEAVY DUTY TRUCK SHOP MANUAL

Summary of Contents for 70 Series 1970

Page 1: ...CHEVROLET HEAVY DUTY TRUCK SERVICE MANUAL...

Page 2: ...ection containin more than one major subject is a Table 6T AIR COMPRESSOR AND GOVERNOR 6Y ENGINE ELECTRICAL 7 TRANSMISSIONS AND CLUTCHES of Contents w p h gives the page number on which each major sub...

Page 3: ...vice experience This information should serve not only as a reference for the experienced mechanical force but also as a comprehensive text for training purposes In some cases considerable space is de...

Page 4: ...h sub section when the major section is so divided SPECIFICATIONS Service data fits and tolerances are listed at end of each section or sub section under the head ing Specifications In some cases refe...

Page 5: ...221 18221 19221 5752C JM80 401IVI 478M 13 2 14 2 F090 F120 30DSC 34DSC S L H D S Q H D 5652 w 6041 A u x 385V 401V 7041 A u x M T40 JV70 6V 53N 14 2 F090 F120 34DSC S LH D 385V W 7041 A u x TV70 6V 53...

Page 6: ...Q H D S SH D RT910 RT0913 8516 3B 8716 3B DH90 8 V 71N 14 2 m 2 F120 F160 S LH D S Q H D S S H D 34DSC 34D3C RT910 RT0913 T905A 8516 3B 8716 3B 8552A 8554A 8341 A u x 8345 A u x DI90 6 71N 14 2 F120 F...

Page 7: ...el is located on inside of glove com partment door of steel tilt and conventional cab m odels This label lists all special equipment installed on the vehicle This information is imprinted on the label...

Page 8: ...bol S19 on C h a r t s 23 Power Steering System 23 Allison Automatic T r a n s m is s io n 24 Hydraulic Oil Special Symbol S23 on Charts Cab Hydraulic H o is t 25 High Temperature Grease Special Symbo...

Page 9: ...LUBRICATION 0 2 CHEVROLET SERIES 70 90 HEAVY DUTY TRUCK SHOP MANUAL...

Page 10: ...nt MPG 1 fitting MPG 1 fitting each joint MPG 1 fitting each joint MPG 1 fitting each joint MPG 1 fitting 1 fitting each e n d MPG Cup or fitting d S27 4 or 8 fittings MPG 1 fitting 1 fitting ea apply...

Page 11: ...LUBRICATION 0 4 CHEVROLET SERIES 70 90 HEAVY DUTY TRUCK SHOP MANUAL...

Page 12: ...apter Cable 1 fitting MPG 6 000 16 Battery Term inals Keep coated S3 6 000 17 Transm ission Shift Rod U Joint 1 fitting each joint MPG 6 000 18 Clutch R elease Cross Shaft 1 fitting each e n d MPG 6 0...

Page 13: ...LUBRICATION 0 6 CHEVROLET SERIES 70 90 HEAVY DUTY TRUCK SHOP MANUAL...

Page 14: ...Linkage Clark 6 0 0 0 22 Auxiliary Trans Shift Tower d 1 fitting MPG 6 0 0 0 23 Auxiliary Trans Shift Levers d MPG 6 0 0 0 24 Transm ission Shift Rod U Joints d 1 fitting each joint 6 0 0 0 25 Hand Br...

Page 15: ...rake Camshafts c 1 fitting e a c h MPG 6 0 0 0 6 Brake Shoe Roller Pins c Apply E 2 0 0 0 0 7 Wheel Bearings Hand pack or use lubricator MPG 2 0 0 0 0 a 8 Axle Shift Unit 2 or 3 Speed c To level of fi...

Page 16: ...and in s ta ll 7 Distributor c l A turn of cam lu b rica to r Breaker pivot 1 d ro p E Rotor felt 4 d r o p s E 8 Generator No lubrication required 9 Starter See instructions E 10 Power Steering Rese...

Page 17: ...art when oil cooler is drained 14 quart Lubrifiner is standard equipment Crankcase capacities are for normal refill Add oil as indicated when oil filter is drained and element changed Capacities given...

Page 18: ...ines IMPORTANT Non detergent and other lower quality engine oils are specifically not recom mended in gasoline engines BREAK IN OILS AND ADDITIVES The use of proprietary blends of supplement ary addit...

Page 19: ...lacedwithS A E 30 as soon as possible MULTI VISCOSITY TYPE ENGINE OILS M ulti Viscosity lubricating oils as a group are not normally recommended However some may be effectively used to facilitate star...

Page 20: ...tim e of an oil change must be taken as an indication that the detergency of the oil has been exhausted When this occurs the oil drain interval should be shortened Since abrasive dust metal particles...

Page 21: ...acity Luber Finer Element Part No Element Part No 500C 750C 2 Gallons 3l A Gallons 2122 2095 2333078 2455358 7 With engine crankcase filled to normal oil capacity FULL mark on dipstick start and run a...

Page 22: ...the ventilation valve s should be checked for proper operation as described in GASOLINE ENGINES SEC 6A under crankcase ventilation system Every 12 000 m iles or 12 months whichever occurs first the va...

Page 23: ...ithin the crankcase Breather tube on 6 71 engines is attached to governor and requires no periodic maintenance Crankcase ventilation on V8 71 engines fig 14 is accomplished by a breather separator and...

Page 24: ...m es lubricated by gear oil instead of wheel bearing grease NOTE Refer to Gear Oil for front wheel bearing lubrication REAR WHEELS 1 Rotate wheel until pipe plug in axle shaft flange is at bottom Vehi...

Page 25: ...tion a magnetic plug is located at left upper front side of case which must be removed and cleaned at regular drain intervals Use S A E 90 above 0 F or S A E 80 when temperature is below 0 F CHECKING...

Page 26: ...r plug NOTE On Spicer compound transm issions remove two drain plugs one each in forward and rearward housings MULTI PURPOSE GREASE SYMBOL MPG ON CHARTS The lubricant indicated by the symbol MPG on ch...

Page 27: ...e of lubricant is marketed by many oil companies Multi Purpose oil MPO previously des cribed may be used to replenish steering gear housing when additional lubricant is required however lubricant as d...

Page 28: ...time of assem bly after overhaul as indicated in various sections of this manual AUTOMATIC TRANSMISSION FLUID SYMBOL SI 9 ON CHARTS R General Motors DEXRON Automatic Trans m ission Fluid Part No 1050...

Page 29: ...at 12 000 mile intervals Drain while fluid is at operating temperature 160 F min 1 Remove bolt nut and strap which secures filter cover to oil pan 2 Carefully remove filter cover to prevent oil gushin...

Page 30: ...sem bly must be replaced HYDRAULIC OIL SPECIAL SYMBOL S23 ON CHARTS The fluid indicated by the symbol S23 is a special hydraulic fluid meeting MIL H 5606B spec ification or equivalent which is satisfa...

Page 31: ...e satisfactory STOPMASTER BRAKE UNIT At time of assem bly after overhaul apply above lubricant to areas indicated in AIR BRAKES SEC 5B of this manual IMPORTANT The use of proper engine oils and oil ch...

Page 32: ...stem is provided beneath center console access oanel on Alum Tilt models GENERAL MAINTENANCE NOTE This section includes general maintenance information on subjects which are common to all cabs Subject...

Page 33: ...orrosion or paint damage corrective m easures should be im mediately employed as described later in this section INTERIOR CLEANING Care of upholstery and interior panels is a relative sim ple but impo...

Page 34: ...Co or Dioxidine American Chemical Paint Co or equivalent is recommended in preparing steel for painting These m aterials vary in method of application and use and should be employed only as directed b...

Page 35: ...here anodized aluminum panels are to be matched ALUMINUM CAB FRAME AND PANEL REPAIRS CAB FRAMING General Information Principle cab framing is composed of box type members of welded aluminum constructi...

Page 36: ...cape chisel before cutting off head with a flat chisel Patch Repairs Small area cab punctures may be covered with sm all patches of sheet aluminum sealer and self tapping screw s Cut patch to amply c...

Page 37: ...ff ends of build up to conform to edge of glass otherwise glass breakage may occur originating at a point adjacent to the end of flange build up INSTALLATION Be sure flange around cab opening is strai...

Page 38: ...ile proceeding around window Use a hitching movement to avoid elong ation of insert 6 Cut off end of insert allowing sufficient overlap for a tight joint then butt into groove REAR WINDOW GLASS REPLAC...

Page 39: ...ype control for operation of windshield washers WIPER ARM ADJUSTMENT To adjust sweep of blades to provide maximum visibility turn on wipers then note sweep of arm s Figure 5 Wiper Arm Installed Steel...

Page 40: ...m Disengage end of rod from arm NOTE Alternate methods of obtaining access to these two nuts are to move the wiper motor forward from the cowl opening or to remove the ash tray panel 5 Using a short c...

Page 41: ...attaching linkage and wiring harness WIPER MOTOR REPLACEMENT STEEL TILT CAB MODELS REMOVAL Figs 5 and 10 1 Remove hex crown nut and lock washer which attaches wiper arm to knurled driver and pivot sh...

Page 42: ...mounting bracket suf ficiently to allow access to connecting link retain ing rings 3 Remove connecting link retaining rings then remove link Separate motor from mounting bracket 4 The transm ission s...

Page 43: ...tch to HIGH speed posi tion opens the shunt field circuit to ground at dash switch and keeps the armature circuit closed to ground The shunt field current must then pass through a resistor located on...

Page 44: ...check for a grounded lead at No 1 or 3 term inals fig 13 or for a grounded shunt field Wiper Inoperative 1 Check wiring harness connections at motor and at dash switch 2 Check fuse if used or circuit...

Page 45: ...separate motor assem bly from gear box housing 2 Remove brush tension by placing brush spring in holder groove as shown in figure 15 3 Slide armature and end plate from motor frame and field Note arra...

Page 46: ...cylinder housing The piston type pump Figure 18 Separating Pump from Motor provides higher pressures and increased volume fig 2 0 The basic principle of operation is very sim ilar to past model pumps...

Page 47: ...click is heard proceed to Step 5 4 If correct voltage was found in Step No 3 connect a jumper wire from washer terminal No 1 to ground fig 19 and operate wiper If washer relay click is heard and pump...

Page 48: ...oves Also be sure triple O ring is properly installed between valve body and pipe assem bly Hose connections on pipe assem bly should be pointed in same direc tion as original position AIR OPERATED WI...

Page 49: ...unit to cowl bracket Separate the wiper motor from cowl for access to linkage connection at motor crank or separate connection from rear side of cowl Remove transm ission and link If desired the link...

Page 50: ...blow smoke through the other this will reveal the point of leak age if any If air line is satisfactory turn on wiper reg ulating valve to diagnose motor trouble as follows IMPORTANT Be sure cover posi...

Page 51: ...T F E LT WASHER RETAINING WASHER SCREW WITH LOCKWASHER PISTON PACKING GEAR ASSEM VALVE STOP UNIT ASSEM GEAR RACK PISTON HEAD VIEW B PISTON ASSEMBLY VIEW C FPDP VALVE HEAD VIEW D SHIM GEAR RACK ASSEMBL...

Page 52: ...undisturbed unless motors fail to function Before removing motors check control valve tubing and connec tions for plugging or leakage Make sure that ade quate air pressure is delivered to motors W IPE...

Page 53: ...rom beneath dash 5 R everse removal procedure to install Be sure to apply a sm all amount of high temperature zinc oxide lubricant to pivot shafts and linkage connections Also apply sealing compound b...

Page 54: ...aft assem bly from motor assem bly 3 Remove four bolts which attach mounting bracket assem bly to motor Remove bracket 4 Remove four screw s which attach wiper control valve body to motorpistonbody as...

Page 55: ...s then remove parking end plates and gaskets from valve body Remove discs from end plates Figure 29 Gear to Piston Rack Timing Marks 2 Unscrew valve pin projecting from valve body side 3 Push out pri...

Page 56: ...ve assem bly should be replaced To assem ble follow reverse order of removal procedure Be sure to apply wiper motor lubricant to all moving parts especially valve surfaces and rubber O rings INSTALLAT...

Page 57: ...luid IMPORTANT Keep reservoir full and add correct amount of washer solvent to prevent freez ing Operate washer pump several strokes to be sure solvent is in lines Use GM OPTIKLEEN as directed MAINTEN...

Page 58: ...ore positive sealing around the door when closed The one piece roof panel has longitudinal ribbing to stiffen and reinforce the roof The floor panel also of one piece construction elim inates joints p...

Page 59: ...the cab sill and the fram e side rail as shown in figure 3 At regular intervals all cab mountings should be checked for loose attaching parts and for deter iorated or collapsed rubber cushions Any on...

Page 60: ...and seat adjusters do not release simultaneously lengthen or shorten adjuster lock rod underneath the seat assembly A stud adjustment nut and wing nut at ends of seat back fram e fig 4 provide a means...

Page 61: ...oval or installation of shims in serted between door and hinge strap fig 5 The door when properly located in door open ing will have equal clearance around itsperim eter TO POSITION DOOR FORE AND AFT...

Page 62: ...eadings NOTE Periodically check tightness of striker bolt Figure 9 Relocating Striker Bolt STRIKER BOLT REPLACEMENT Removal Refer to Fig 7 1 Mark position of strik er bolt spacer or washer on door pil...

Page 63: ...d aft adjustment is obtained by use of shim spacers located between the bolt washer and the cab pillar Figure 7 illustrates location of bolt w ashers and spacer Striker Bolt Fore and Aft Adjustment 1...

Page 64: ...After obtaining proper height adjustment pro ceed to make Door Rear Edge In or Out Ad justment Figure 14 Installing Access Panel Insert DOOR CHECK REPLACEMENT IMPORTANT Do not allow door to swing beyo...

Page 65: ...er seal around opening indoor 2 Place access panel to seal then with hook end of tool in panel groove of seal move tool around panel to force outer lip of seal over edge of panel 3 Thread end of sm al...

Page 66: ...ooves of lock cylinder If one of the retainer legs is not engaged the retainer flange will not be vertical indoor slot DOOR INSIDE HANDLES REPLACEMENT NOTE If removing door lock inside handle the hand...

Page 67: ...hed two rods out through access opening in door 7 Separate rods from lock mechanism if de sired To disengage pull rod fastener force lock tab of fastener outward through sm all hole in lock release le...

Page 68: ...ft resistant latch Friction mechanism consists prim arily of a coil spring mounted on vent window lower pivot which exerts frictional force against mounting lower support If friction mechanism is adju...

Page 69: ...on of vent assembly to door inner panel brac ket fig 23 4 Referring to figure 23 install three screws to attach vent fram e to door structure 5 Adjust the vent opening and closing tension as directed...

Page 70: ...door fram e 2 If the glass horizontal seal strips were removed from door p ress new seal strips into position making sure all strip attaching clips are fully engaged 3 Lower the door window assembly i...

Page 71: ...nimum capacity a sling having padded hangers and two or more support blocks to rest cab on once the cab is removed from chassis 1 Disconnect the battery 2 Remove the hood panels 3 Drain cooling system...

Page 72: ...control must be posi tioned all the way towards the right in order to obtain heat IMPORTANT Do not operate the blower motor when AIR control lever is in the full left position The heater fan speed is...

Page 73: ...CAB AND BODY MOUNTINGS 1 42 AIR HEATER CONTROLS T 2428 figure 30 Air Flow Heater CHEVROLET SERIES 70 90 HEAVY DUTY TRUCK SHOP MANUAL...

Page 74: ...er to Figure 30 The air distributor can be readily replaced after disconnecting the attaching air hoses and the DEFROST control w ire then removing the three screw s which attach distributor to dash a...

Page 75: ...st seal the link rod under dash can be bent slightly as re quired to increase the closing pressure NOTE Do not bend rod excessively as the control handle will fail to rem ain in closed detent position...

Page 76: ...nel at rear of passenger seat and at top of seat back riser A concealed step is constructed in floor of each door opening Also a central island shifting area that is not disturbed with the cab tilted...

Page 77: ...b safely in full tiltposition IMPORTANT Make sure check link is proper ly engaged with fram e anchor pin TO LOWER CAB Fig 2 IMPORTANT Before lowering the cab to oper ating position make sure transm is...

Page 78: ...m e The rear mounting also includes an additional safety catch Tightness of cab hold down lock can be adjusted by shortening or lengthening catch release rod After adjusting Figure 5 Driver s Seat Mou...

Page 79: ...ade in sequence described in the following paragraphs REPOSITION DOOR UP OR DOWN Fig 7 Door up and down adjustment in cab open ing is provided by means of floating hinge cap screw tapping plates withi...

Page 80: ...n of strik er bolt spacer or w asher on door pillar using pencil or crayon Figure 9 Sight Checking Striker Bolt Alignment 2 Insert a 5 16 inch hex wrench into head of strik er bolt then turn bolt coun...

Page 81: ...k cam as shown in left view of figure 10 2 Smear some grease or paint on contact edge of lock cam as shown in same view 3 Slowly close door until cam barely contacts the striker bolt to leave an im pr...

Page 82: ...Fig 14 1 Remove access panel at bottom of door 2 Through access panel opening pull lock cylinder retainer from beneath the lock cylinder grooves by grasping retainer lip with pliers 3 Tilt lock assemb...

Page 83: ...le the handle posi tion should be marked in relation to door panel to assure that handle is installed later at the same operating angle REMOVAL Fig 15 1 Insert tool J 9886 between handle flange and es...

Page 84: ...provide clearance for re moval of lock mechanism 7 At rear edge of door remove three special locking type screw s which attach lock mechanism to door fram e Lower the lock and attached two rods out t...

Page 85: ...door just below vent window 4 Remove fram e to door screw and fram e to divisional channel screw fig 16 5 Remove three division channel lower at taching screw s fig 16 6 Remove division channel screw...

Page 86: ...e applicable screws which attach either division channel or run channel to door framing fig 16 and lower channel s through access opening at bottom of door 3 Install channel s in reverse order of re m...

Page 87: ...oapstone side away from glass around edge of glass P ress glass with glazing rubber into lower channel then p ress upper channel over top of glass Make sure channels are firm ly seated then install tw...

Page 88: ...of outlet door provides positive sealing of outlet Seal which is glued to door can be readily replaced if necessary CONTROL ADJUSTMENT DRIVER S SIDE NOTE Refer to inset of figure 27 When control knob...

Page 89: ...tilt cab approximately 45 to the unloaded position of cab mounting torsion bar refer to preceding caution and suspend safely there While cab is in this posi tion insert a pry bar in between cab right...

Page 90: ...t Lever Installed and all electric connectors that junction with the cab to chassis 9 Connect accelerator linkage and adjust as outlined under ENGINE FUEL SYSTEM SEC 6M Connect all ground straps 10 Co...

Page 91: ...ed in LUBRICATION SEC 0 8 Raise and lower cab to check operation If cab rises too fast from operating position or if considerable effort is required to raise cab make torsion bar tension adjustment as...

Page 92: ...set Formed sheet aluminum outer panels are sealed and riveted to major cab frame members Cab front upper panel is a formed aluminum stamping incorporating openings for heater inlet radiator grill and...

Page 93: ...atch is also provided as part of the hold down system Stamped on the top of the pump control valve are the letters DN and UP When the cab is in normal driving position place lever in UP position When...

Page 94: ...esult of the unique design of the tilt lever mechanism the cab can be secured in any position from full tilt to full down CAUTION LOCK PIN MUST BE INSERTED IN SLIDE CHANNEL WHENEVER CAB IS IN A RAISED...

Page 95: ...figure 5 Hydraulic oil is drawn f r o m reservoir through suction screen 21 and inlet check valve 19 due to upward movement of pump piston 4 as pump handle 10 and beam 9 are raised Oil is pulled into...

Page 96: ...d immediately has to pass through the screen 3 This filters out any dirt that may be caught in the hose when the hoses are assembled to the system The oil then passes through a hollow set screw and ch...

Page 97: ...ssures through a wide tem perature range This is necessary to assure correct operation of velocity safety fuses and proper back fill of cylinder during controlled fall portion of tilt cycle TILT CYLIN...

Page 98: ...h strap wrench and then tighten cap to cylinder fig 11 7 Install hydraulic line fitting in cap if p re viously removed Connect hydraulic line and bleed as described later Figure 10 Tilt Cab Lock SPRIN...

Page 99: ...control valve pump lever in DN position and slowly actuate pump handle until air free oil flows from loose connection at tilt cylinder Tighten connection firm ly 6 Fill pump reservoir until oil flows...

Page 100: ...ght rear mounting has an adjoining safety catch MAINTENANCE No system atic service is required other than a periodic check of mounting attaching bolt torques Refer to figures 8 and 10 for bolt torques...

Page 101: ...e event of special equipment disconnect linkage at most convenient point 17 Lower cab after placing wooden blocks in the V of both re ar mountings to prevent cab locks from latching 18 Remove radiator...

Page 102: ...p screws Tighten cap screw s to 20 25 foot pounds torque after adjusting door in cab opening as described later under DOOR ADJUSTMENTS Reconnect door window control wiring harness if used DOOR ADJUSTM...

Page 103: ...hould not be closed completely until a visual check is made to determine if lock cam will engage the striker bolt correctly Center of striker bolt should be in direct alignment with V slot in door See...

Page 104: ...rly positioned door will be difficult to close and an extra load will be placed on hinges which could pull door out of alignment To make positive check perform the following 1 Mark a horizontal line t...

Page 105: ...sser quality or substitute design Torque values must be used as specified during reassem bly to assure proper retention of this part DOOR RELEASE AND LOCK CYLINDER REPLACEMENT The outside door release...

Page 106: ...lock mechanism and remote control are located at cab pillar Both components should be removed at the same tim e REMOVAL Fig 21 1 Remove door release inside handle and escutcheon plate as instructed pr...

Page 107: ...Removal 1 Lower window to full down position 2 Remove cross recessed screw s w h i c h attach trim panel to window regulator motor housing 3 Remove cross recessed screw s which at tach motor housing t...

Page 108: ...gure 24 Use either a push or pull type spring scale positioned perpendicular to re a r edge of vent glass 3 Install trim panel to lower quarter of door DOOR VENT WINDOW ASSEMBLY REPLACEMENT REMOVAL Fi...

Page 109: ...oapstone side away from glass around glass e Brush inside of channel with a light appli cation of liquid soap solution to facilitate install ation DO NOT USE GREASE OR OIL f P ress channel on filler a...

Page 110: ...o install p ress seal assembly evenly into door panel 4 Install door glass DOOR WEATHERSTRIP REPLACEMENT Cab door sealing consists of a moulded rubber w eatherstrip cemented around entire pe riphery o...

Page 111: ...ation lever and raise or lower seat to desired position 3 To adjust seat back lift or push down on tilt lever and position seat back to desired angle Standard Seat Replacement Fig 31 1 Through opening...

Page 112: ...or damage that could lessen the effectiveness of the restraint system If neces sary to replace lap belts or related fasteners refer to GENERAL CAB MAINTENANCE SEC 1A of this manual Figure 33 Air Suspe...

Page 113: ...1A at beginning of this group for applicable information on straightening dinging refinishing and painting of cab components IMPORTANT Always wear heavy type gloves to prevent possible injury when ha...

Page 114: ...ally pry outer moulding away from cab front panel Be careful not to bend moulding or damage cab paint 3 To install carefully snap outer moulding and clip retainers in place Position inner mould ing on...

Page 115: ...der Tighten all attaching bolts and nuts firm ly OUTSIDE MIRRORS Two types of side m irrors are offered The left view of figure 39 illustrates the 6 x 16 west coast type the right view illustrates the...

Page 116: ...si tion m irror on head and install retainer Replace rubber moulding around head Head Tension Adjustment By loosening wing nut on head end of arm m irro r head ball stud may be repositioned in mount i...

Page 117: ...ENT Fig 40 1 From inside luggage compartment remove three screw s which retain latch rod cover to front panel 2 Remove nuts that retain latch rod brackets to compartment ceiling Remove latch rod and b...

Page 118: ...ant is force circulated through heater core s as a result of pressure from engine water pump For the standard cab hot coolant from bottom of water filter flows through a flexible hose into main heater...

Page 119: ...HECIR HTR HTR DEF HOT TEMP COLD BLOWER HEATER HOSES BLOWER I I H MAIN HEATER AIR FLOW TO HEATER OUTLETS BELOW DASH TO DEFROSTER OUTLETS ABOVE DASH HEATED AIR FLOW _ _ _ CONTROL CABLES ELECTRICAL WIRIN...

Page 120: ...ab air 2 Should defogging of windshield be required open fresh air ventilator door slightly place HTR lever to DEF and operate blower at high speed 3 For warm weather ventilation le ss air conditionin...

Page 121: ...clamps are located immediately to the rear of sleeper compartment bulkhead 8 Loosen plastic clamps retaining heater and defroster duct hoses to air distributor assem bly Remove air conditioning outlet...

Page 122: ...d Heater Cover Replacement 3 Drain and disconnect coolant lines from main heater housing 4 Disconnect all control cables and electrical leads which would interfere with removal of main heater housing...

Page 123: ...ess panel and heater cover as heater core removal Refill cooling system described previously in this section under Con 7 Connect battery ground cable sole A ccess Panel andHeater Cover Replacement CAB...

Page 124: ...clear rivet heads IMPORTANT Do not use spacers to raise sills above rivet heads If body longitudinal sill is of metal it will be necessary to use a one piece full length hardwood strip with holes to...

Page 125: ...vet heads 6 To prevent mounting clip plate becoming embedded in longitudinal sill install a sheet metal channel on top of sill at each mounting point figs 1 2 and 3 Rabbet grooves along each side of t...

Page 126: ...nal sills attach sills if possible as shown in figure 3 since mounting on cross sills bolsters is not recommended Longitudinal sills can be easily made of dry hardwood and attached to either wood or m...

Page 127: ...B AND BODY MOUNTINGS 1 96 IMPORTANT DO NOT drill additional holes in frame DO NOT weld heat treated frame Refer to FRAME SEC 2 for additional cautions CHEVROLET SERIES 70 90 HEAVY DUTY TRUCK SHOP MANU...

Page 128: ...of air due to vehicle move ment and engine fan The receiver dehydrator bracket mounted to right side of radiator shell or sheet metal is de signed to store liquid refrigerant and to remove sm all trac...

Page 129: ...at the end of this section for trouble shooting the system s AIR CIRCULATION Figs 4 and 5 Outside air enters system through a louvered opening located on vehicle front panel or side cowl opening Air f...

Page 130: ...ND TUBING LOW PRESSURE HOSE HIGH PRESSURE HOSE CONDENSER SIGHT GLASS LOW PRESSURE SERVICE GAUGE VALVE EXPANSION VALVE EQUALIZER LINE EVAPORATOR HIGH PRESSURE SERVICE GAUGE VALVE COMPRESSOR RECEIVER DE...

Page 131: ...NG AIR INLET y i i J COLD AIR OUTLETS CENTER DASH A C BLOWER AND COMPRESSOR SWITCH OUTSIDE AIR INLET TO HEATER OUTLETS BELOW DASH I COLD AIR _ _ OUTLETS TO DEFROSTER FRONT OF OUTLETS ABOVE DASH DRIVER...

Page 132: ...our levers and a four position fan switch All controls are located on the console to the right of the gauge panel 1 The A C lever when moved to the ON position energizes the com pressor clutch coil to...

Page 133: ...warm weather ventilation less air conditioning place A C lever on OFF AIR lever on OUTSIDE HTR lever on HTR TEMP lever on COLD and then place blower switch on High Speed Air flow will be directed thr...

Page 134: ...lower distributor duct under the dash can be pulled downward AIR knob controls flow of outside air through the heater unit Place knob in extreme right p osi tion for heating only HEATER FAN SPEED is c...

Page 135: ...air at normal room temperature it would absorb heat from surrounding air and boil immediately changing to a vapor 5 When heat is removed from water vapor it w ill condense back into a liquid For examp...

Page 136: ...ne never fill the drum completely Space should always be allowed above the liquid for expansion Weighing drums before and during the transfer w ill determine fullness of drums Discharging large quanti...

Page 137: ...the equalizer line provide the temperature regu lation of the expansion valve This capiilary tube is fastened to the low pressure refrigerant pipe coming out of the evaporator so that it communi cates...

Page 138: ...CAB AND BODY MOUNTINGS 1 107 Figure 8 Air Conditioning and Heater Control Aluminum Tilt Cab Model CHEVROLET SERIES 70 90 HEAVY DUTY TRUCK SHOP MANUAL...

Page 139: ...R TEMPERATURE CONTROL SUCTION THROTTLING VALVE AIR TEMPERATURE CONTROL CABLE SUCTION THROTTLING CONTROL CABLE AIR CONTROL CABLE T 6885 Figure 9 Air Conditioning and Heater Control Conventional Cab Mod...

Page 140: ...GS 1 109 DISTRIBUTOR BOX BLO W ER AIR INLET ASSEMBLY REAR DUCT X FRONT DUCT CENTER DUCT AIR INTAKE DUCTS T 6944 Figure I 0 Heater and Air Intake Aluminum Tilt Cab Model CHEVROLET SERIES 70 90 HEAVY DU...

Page 141: ...ASSEMBLY MANIFOLD ASSEMBLY SEAL EVAPORATOR CORE ASSEMBLY EXPANSION VALVE HEATOR EVAPORATOR AND CORE ASSEMBLY CONNECTING TUBES DOOR CONTROL BRACKET MOTOR AND M OUNTING PLATE CORE RETAINER T 6886 Figure...

Page 142: ...BODY MOUNTINGS 1 111 THERMO EXPANSION VALVE DRIVER S A C AND DEFROSTER DISTRIBUTOR T 4945 Figure 72 Air Conditioning and Defroster Aluminum Tiff Cab ModelI CHEVROLET SERIES 70 90 HEAVY DUTY TRUCK SHOP...

Page 143: ...CAB AND BODY MOUNTINGS 1 112 Figure 13 Air Conditioning Air Outlets and Hoses IConventional Cab Model CHEVROLET SERIES 70 90 HEAVY DUTY TRUCK SHOP MANUAL...

Page 144: ...which cools and dehumidifies the air before it enters the cab High pressure liquid refrigerant flows through the valve orifice in the expansion valve into the low pressure area of the evaporator This...

Page 145: ...able operated from the instrument panel to the lever arm on the valve When reduced load conditions require elevated control pressures the lever arm actuates the inner spring assem bly causing the pist...

Page 146: ...pulley a s sembly rearward toward the pulley As the arm ature plate moves toward the pulley it contacts the pulley shaft face which rotates freely about the com pressor shaft When the AIR COND knob i...

Page 147: ...collapse soon after the clutch has been discon nected Foam may be noted in the sight glass below 70 F even when the system is free of air and properly charged Details of these conditions are in the I...

Page 148: ...6000 M iles whichever occurs first 1 Check front of condenser for an accumula tion of dirt such as leaves bugs dirt etc Also check to see that the space between the condenser and radiator is also fre...

Page 149: ...ystem is sealed from the atmosphere and remains under pressure at all tim es Regardless of whether or not the sy s tem is charged it must remain sealed to prevent entrance of contaminants such as air...

Page 150: ...les present in sight glass System low on charge Check with leak de tector Correct leak if any and fill system to proper charge No bubbles Sight glass clear System is either charged or empty Feel high...

Page 151: ...d since it is neither repairable nor adjustable 29 5 psig 30 0 psig 30 5 psig 31 0 psig 31 5 psig 32 0 psig Sealevel 1 0 0 0 ft 2 0 0 0 ft 3 000 ft 4 000 ft 5 000 ft 32 5 p sig 6 000 ft 33 0 p sig 7 0...

Page 152: ...air stream 5 Place a second calibrated thermometer in auxiliary fan air stream to measure wet bulb temperature 6 Connect engine tachometer 7 Open all air outlets below dash 8 Locate a calibrated ther...

Page 153: ...are previous test with system pressures and temperature shown on Operational Test Data Chart fig 19 If not within the lim its shown re fer to the Insufficient Cooling Diagnosis Chart for possible caus...

Page 154: ...ittings using J 5420 Schra der valve adapter at the suction gauge fitting and J 9459 Schrader valve adapter at the discharge gauge fitting 3 Crack open the high pressure valve on man ifold gauge set t...

Page 155: ...ed 4 Start the vacuum pump and slowly open the low and high pressure sides of the manifold gauge set to avoid forcing oil out of the refrigeration system and the pump Pressure is now being re duced on...

Page 156: ...rigerant drum upside down as this would allow liquid refrigerant to enter compressor which may cause damage 4 Open valve on refrigerant drum and both valves on gauge set to allow refrigerant to flow i...

Page 157: ...eady for charging 3 Connect center flexible line of gauge set to the fitting on a can opener valve NOTE If line at center gauge fitting has not been purged of air loosen line at center fitting on gaug...

Page 158: ...r 15 minutes after the sy s tem reaches 26 28 inches vacuum NOTE in all evacuating procedures the sp eci fication of 26 28 inches of mercury vacuum is used These figures are only attainable at or near...

Page 159: ...d immediately shut off valve at gauge set or on refrigerant drum Check weight of refrigerant drum and pail of water Then slowly open valve on gauge set or refrig erant drum and add one more pound of r...

Page 160: ...p from cylinder 2 Close valve knob on detector unit 3 Thread detector unit onto top of fuel cylin der Tighten finger tight 4 Attach search hose assem bly to detector unit fig 24 5 Open control valve u...

Page 161: ...uld be used for determining leaks ELECTRONIC LEAK DETECTOR An electronic leak detector for detecting re frigerant leaks is also available Instructions for operation of this type detector are supplied...

Page 162: ...f moisture in the system replace the receiver dehydrator assem bly and flush all com ponent parts or replace if necessary After flush ing refrigeration system in this manner the full oil charge should...

Page 163: ...harge of the refrigerant system on new com pressor in space on plate pro vided for this information NOTE Follow procedure for replacing oil in new com pressor explained previously under Re moving Malf...

Page 164: ...LEAKING SEALS AND HOSES When refrigeration system components other than the com pressor are replaced the com pressor must also be removed and oil drained from the com pressor if oil was sprayed in cop...

Page 165: ...n panel access cover to panel reinforcement brace console panel and heater cover Remove access cover from cab 3 Loosen screw s retaining heater cover to panel reinforcement and console panel Remove ai...

Page 166: ...rator Heater Core and Blower Replacement 4 Evacuate and charge system 5 Make a performance test P O A VALVE REPLACEMENT ALUMINUM TILT CAB Refer to Figures 1 and 3 NOTE When refrigeration system compon...

Page 167: ...oolant 3 Disconnect battery ground cable or pull m aster circuit breaker switch on instrument panel 4 Disconnect inlet line to expansion valve and outlet lines to P O A valve Cap all openings 5 Discon...

Page 168: ...r 5 Disconnect all heating and cooling control cables A lso disconnect blower motor ground wire at dash 6 Disconnect refrigerant hoses from unit 7 At base of unit pull the drain tube from floor openin...

Page 169: ...would indicate internal damage to the com pressor If no foreign matter is found in oil com pressor can be used Flush entire refrigeration system with re frigerant drain oil from com pressor and pour...

Page 170: ...ng a light coat of rubber cement NOTES ON STORING AND INSTALLING A C COMPONENTS 1 All sub assem blies are purged and sealed before shipment Shipping caps should not be removed until just prior to maki...

Page 171: ...rant tubes or air fins See Note B If ice is blocking evaporator check P O A valve function or adjust s T valve If cooling rem ains low follow diagnosis under Normal Evaporator P ressure If P O A valve...

Page 172: ...s high after depressurizing the system continue depressurizing until bubbles appear in the sight glass If suction pressures also remain high then the P O A or suction throttling valve may require repl...

Page 173: ...Ohm s at 8 0 3 85 Am ps at 8 0 3 2 12V System Capacities Refrigerant Alum inum Tilt C ab 4 lb 8 oz Refrigerant Conventional C a b 3 lb 4 oz 525 Viscosity Refrigerant Oil Entire S ys te m 11 fluid oz...

Page 174: ...be used on the right rail The illustration fig 1 is used m erely to serve as a guide in the selection of checking points M In order to obtain reliable results checking must be done thoroughly and acc...

Page 175: ...following restrictions should be ad hered to completely 1 Frame straightening should be attempted only by experienced personnel 2 Heat may be applied to S A E 950 or S A E 1023 steel only by competen...

Page 176: ...nding moment failure will occur at different areas on various types of vehicles therefore for easier understanding the effects of excessive bending mo ments will be discussed by type of vehicle TRACTO...

Page 177: ...r installation of fifth wheels or bodies is covered in the Body Builder s Book however it should be re em phasized that the use of U bolts for attachment of fifth wheels or bodies is not an approved i...

Page 178: ...ng a reinforcement plac ed on the web section of the fram e rail or for add ing gussets or plates tocrossm em bers Continuous fillet welds should never be made across frame flanges or along inside edg...

Page 179: ...and should not be readily discernible from the unre paired area of side rail Use a copper spacer be tween the flanges of cracked base rail flanges and reinforcement flanges and repair each flange sep...

Page 180: ...ail and can be full length or a localized reinforce ment The principle disadvantage of the channel is additional weight and hours of labor required to make an installation Additional difficulty may ar...

Page 181: ...his section how ever the importance of adhering to them cannot be overemphasized 1 Always identify the material of base rail 2 Frame straightening or repair must be at tempted only by highly qualified...

Page 182: ...ug a y Vs 1 V s V i lVs 7 l6 y s m a V i 1 3 S 9 l6 1 V 2 3 l6 S A E 950 HIGH STRENGTH LOW ALLOY STEEL Trade Name Type Source N A X Great Lakes Steel jalten 1 Jones Laughlin Steel Company Republic Dou...

Page 183: ...FRAME 2 10 Frame repairs should be undertaken only by competent mechanics and only the recommended m aterials should be used CHEVROLET SERIES 70 90 HEAVY DUTY TRUCK SHOP MANUAL...

Page 184: ...dicates points at which alignment dimensions are taken The caster camber and toe in dimensions are for vehicle at design load with frame level If frame is not level on alignment equipment the frame an...

Page 185: ...t 4 Check steering tie rod and drag link ends for looseness 5 Check kingpins for looseness CHECKING AND CORRECTING FRONT WHEEL TOE IN Incorrect toe in results in excessive tire wear caused by side sli...

Page 186: ...ring knuckle bushings and king pins as instructed in FRONT AXLE SEC 3B 2 Check the wheel run out as instructed in WHEELS AND TIRES SEC 10 of this manual If run out is excessive straighten or replace w...

Page 187: ...r reading c Negative frame angle must be subtracted from negative caster reading d Positive frame angle must be added to negative caster reading Example An HM 7500 with F070 axle and power steering ha...

Page 188: ...20 39 39 27 45 27 45 5 45 5 45 6 15 6 15 TV70 1 30 30 0 15 30 0 15 30 1 30 30 0 15 30 0 15 30 1 15 30 1 15 30 1 15 30 Vie to Vs Vie to Vs Vi6 to Vs Vs to Vi l s to Vi Vs to Vi F 070 F 090 F 120 39 39...

Page 189: ...enlarged Refer to figure 4 NOTE The shorter draw key is used in the upper position Check the vertical movement of knuckle in relation to axle center If movement exceeds 0 005 add one or more service...

Page 190: ...installed in the steering knuckles and stop against the axle center as shown in figure 5 on F 070 F 090 F 120 and FE 970 axles On F 160 axles stop screw s are in stalled on axle center and stop pads...

Page 191: ...GS SEC 3C 2 Install hubs and bearings as described in FRONT HUBS AND BEARINGS SEC 3D Con nect drag link as directed in STEERING SYSTEM SEC 9 of this manual Connect brake lines If hydraulic brakes are...

Page 192: ...shim thrust bearing and axle center end P ress pin down until m illed slot in pin lines up with draw key hole 7 Insert draw key into axle center register ing with kingpin then install lock washer and...

Page 193: ...cannot be overstress ed If king pins and bushings are installed with particles of dirt or metal between bearing sur faces excessive wear will result necessitating premature replacement of parts 1 Refe...

Page 194: ...st not ex ceed 0 005 inch Spacing shim s are available in 0 005 0 010 and 0 015 thickness 5 After positioning the proper shim align the flats on kingpin to align with draw key holes in axle center the...

Page 195: ...e d s o l v e n t C A U T IO N A vo id turn ing bearings in races w hen bearing assem blies are d irty sin ce sm all p articles o f g rit w ill damage bearings S p e c ifi c a tio n s at end o f th is...

Page 196: ...RQUE SPECIFICATIONS King Pin Nut King Pin Bearing Cap Cap Screw 60 70 In Lbs 250 Ft Lbs Then Advance to Next Cotter Pin Hole 350 390 Ft Lbs 60 70 In Lbs AXLE MODEL FI 20 F160 KING PIN Length Diameter...

Page 197: ...n fittings Refer to LUBRICATION SEC 0 of this manual TIGHTENING At regular intervals spring U bolts should be checked and tightened if necessary to torque listed in Specifications at end of this secti...

Page 198: ...FRONT SUSPENSION 3 15 Figure 1 Front and Rear Mountings Front Spring Typical CHEVROLET SERIES 70 90 HEAVY DUTY TRUCK SHOP MANUAL...

Page 199: ...ughly clean the spring eye bushings bracket or shackle bushings and shackle or brac ket bolt or pins to remove all old lubricant Make sure lubrication passages in bolts and pins are open 2 Insert bolt...

Page 200: ...of this section Test fit of bolts or pins in respective bushings before installing springs SPRING LEAF REPLACEMENT EXCEPT OPTIONAL TWO LEAF TYPE 1 Mark down one side of springs to assure original posi...

Page 201: ...enter bolt holes using a suitable drift tool Position C clamp on spring pile adjacent to center bolt holes and tighten clamp 3 Remove drift tool then insert center bolt 1 and install nut tighten firm...

Page 202: ...at front with optional m ulti leaf springs position a flat washer over bolt spacer at each side of spring eye as shown in fig ure 2 3 Raise front end of spring into frame for ward hanger brackets 4 I...

Page 203: ...on tapered springs with shock absorber bracket facing outside rear Install U bolts 1 over spacer and spring 7 Install U bolt washers and nuts 15 Tighten nuts alternately until a torque of 190 to 210...

Page 204: ...ALL 90 ALUM TILT 110 130 FRONT SPRING FRONT BRACKET AND STEERING GEAR BRACKET TO FRAME BOLT NUT HM JM 80 HV JV 70 50 60 CONV CAB 90 50 60 FRONT SPRING REAR BRACKET TO LOWER SILL BOLT NUT ALL 50 60 SHO...

Page 205: ...FRONT SUSPENSION 3 22 GOOD FRONT SPRING AND SHOCK ABSORBER MAINTENANCE PAYS DIVIDENDS IN DRIVER SATISFACTION AND LESS CHASSIS REPAIR CHEVROLET SERIES 70 90 HEAVY DUTY TRUCK SHOP MANUAL...

Page 206: ...is the slightest indication of leakage wear or damage An im perfect seal may permit bearing lubricant to reach brake linings resulting in faulty brake operation and necessitating premature re placeme...

Page 207: ...or to the nearest cotter pin hole in spindle or sufficient ly to allow the wheel to rotate freely within lim its F070 AXLE FI 20 AXLE 6 19 20 V n FI 60 AXLE F090 AXLE 1 Bearing Adjusting Nut 2 Adjusti...

Page 208: ...ections to correctly position the bearings 4 Back off the adjusting nut 1 4 to 1 3 turn making sure the wheel turns freely and is within lim its of 0 001 to 0 007 end play 5 Position lock ring 4 on st...

Page 209: ...135 to 150 foot pounds torque 6 Bend nut lock over one flat of adjusting nut and at opposite side of washer bend flat over lock nut 7 Attach hub cap 1 and new gasket 6 to hub with cap screw s and loc...

Page 210: ...is in place on axle spindle then carefully install hub assem bly on spindle being careful not to damage inner oil seal 7 Place outer bearing cone and roller assem bly on spindle pressing firmly into...

Page 211: ...el Bearing Adjustment Components FE970 Axle wash bearing adjusting nut and washer in cleaning solvent and wipe dry INSPECTION 1 Inspect bearings for excessive wear chip ped edges or other damage Slowl...

Page 212: ...NT If any wheel experiences a single stud failure caused by a loose running wheel all studs should be replaced A loose running wheel may cause only one stud to break but more studs could be fatigued t...

Page 213: ...SUSPENSION 3 30 Replacement of parts which show appreciable wear is more economical than a premature over haul resulting from continued use of worn parts CHEVROLET SERIES 70 90 HEAVY DUTY TRUCK SHOP M...

Page 214: ...ive to several system s used to shift 2 speed and 3 speed axles Information is also included on inter axle differential lock con trols used on the forward unit of some tandem axle units TWO SPEED ELEC...

Page 215: ...ounted to back of speedometer and is electrically connected to control switch When the control switch button is placed in LOW range an electro m agnet shifts the adapter mechanism to compensate for th...

Page 216: ...mounted on the transm ission shift lever and is manually operated by the driver The three speed control switch shown in figure 5 controls air to shift units mounted on each axle The three speed axle s...

Page 217: ...ervals the following lubri cation inspection and maintenance procedures should be accomplished and corrective m easures taken wherever necessary LUBRICATION Lubrication intervals method of filling and...

Page 218: ...ING TROUBLE If the electric shift fails to operate properly the system should be tested and the trouble diag nosed as described in following paragraphs A test light consisting of a 1 2 volt bulb with...

Page 219: ...nection Slide tube nut back on tube and remove all particles of seal ring from tube and from inside of nut Slip new seal ring over tube end Insert tube into connector fitting and seat tube solidly in...

Page 220: ...under frame to prevent accidental dropping of vehicle 2 Disconnect hydraulic or air brake lines whichever is used Refer to BRAKES SEC 5 3 Disconnect electric wiring air lines or line from power shift...

Page 221: ...oll axle into position under vehicle 3 On Hendrickson type suspension connect axle to equalizing beam as directed in REAR SPRINGS SEC 4B 4 On Page and Page type suspension connect axle housing to spri...

Page 222: ...ock Figure 11 Removal or Installation of Thru Shaft Rear Bearing and Retainer washers attaching cover to rear of axle housing Remove cover assem bly with oil seal and bearing fig 11 3 At front of hous...

Page 223: ...i t a t i n g r e m o v a l o f t h e a x l e AXLE SHAFT REPLACEMENT REMOVAL P r o c e d u r e f o r r e m o v a l o f a x l e s h a f t s i s t h e s a m e w i t h a x l e a s s e m b l y r e m o v...

Page 224: ...remove it from axle housing Accomplish in following manner 2 Remove five screw s from shift unit housing cover then remove cover This also drains the lubricant After cover is removed note that drive s...

Page 225: ...while another has the seal installed in a retainer which is then attached to carrier by cap screws REMOVAL 1 Remove propeller shaft from yoke at axle as directed in PROPELLER SHAFTS SEC 4D 2 Hold prop...

Page 226: ...shaft fig 17 2 Position shift cylinder and piston assembly over shift fork shaft 3 Install ring seal over shift fork shaft and into piston counterbore Install washer and nut then tighten nut fig 16 4...

Page 227: ...l s t u d n u t s a t t a c h i n g s h i f t c h a m b e r t o s h i f t h o u s i n g 5 P o s i t i o n s h i f t h o u s i n g a n d c h a m b e r a s s e m b l y t o d i f f e r e n t i a l c a r...

Page 228: ...22 Position of Drive Nut When Disassembling to bracket using snap ring fig 20 2 Install clevis pin attaching diaphragm rod yoke to lock out shift lever Whenever lock holes in yoke and lever do not li...

Page 229: ...ring winding lever 24 unless necessary to replace Figure 25 Removing Motor W tes TP BaC5 Figure 26 Removing Motor one of the parts If necessary to disassem ble mount assem bly in vise as shown in figu...

Page 230: ...r minal the motor will run in one direction With the other motor wire connected to the battery motor will run in the opposite direction The motor has a stall torque of approximately 6 in lbs Clamp a s...

Page 231: ...n s i s t i n g o f s h i f t f o r k a c t u a t i n g l e v e r 2 2 t o r s i o n s p r i n g 2 3 a n d s p r i n g w i n d i n g l e v e r 2 4 h a s b e e n s e p a r a t e d r e a s s e m b l e W...

Page 232: ...t 7 then install gasket 5 on housing Install motor 6 and cover 4 into housing Install three screw s and lock washers 1 and two stop nuts 2 Install motor cover cable clip 3 under outer screw Tighten sc...

Page 233: ...u a t i n g l e v e r f r o m h o u s i n g I N S P E C T I O N 1 I n s p e c t s h i f t f o r k s e a l f o r g o o d c o n d i t i o n a n d t i g h t f i t o n s h i f t f o r k C h e c k s h i f...

Page 234: ...l y 2 R e m o v e c l a m p r i n g b o l t s t h e n s p r e a d c l a m p r i n g a n d r e m o v e 3 R e m o v e c h a m b e r c o v e r a n d d i a p h r a g m 4 P u l l s h i f t r o d a n d p l...

Page 235: ...I S A S S E M B L Y F i g 3 9 1 R e m o v e r u b b e r b o o t f r o m d i a p h r a g m r o d a n d y o k e 2 L o o s e n y o k e n u t t h e n t h r e a d y o k e a n d n u t f r o m d i a p h r a...

Page 236: ...I n s t a l l b o o t a n d y o k e o n d i a p h r a g m r o d INTER AXLE DIFFERENTIAL CONTROL VALVE I n t e r a x l e d i f f e r e n t i a l c o n t r o l v a l v e a s s e m b l y i s u s e d t o...

Page 237: ...l l c o n t r o l l e v e r i n b o d y a n d s e c u r e w i t h f u l c r u m p i n S t a k e p i n i n p l a c e 3 T u r n b o d y b o t t o m s i d e u p a n d i n s t a l l v a l v e d i s c v a...

Page 238: ...i d e o f b r a c k e t o r t h e l o c k s f i t i n t o a g r o o v e i n t h e r e b o u n d p i n R e f e r t o f i g u r e 3 a n d r e m o v e r e b o u n d p i n s 2 I n s t a l l a C c l a m p...

Page 239: ...i l d u p i s n o t r e m o v e d f r o m s p r i n g l e a v e s a t c e n t e r n e a r U b o l t s U b o l t s w i l l e v e n t u a l l y w o r k l o o s e 2 I n s t a l l U b o l t s p a c e r o...

Page 240: ...orber bracket and tighten nuts to torque listed in Specifications at end of this section 8 On other models using pins install fitting and lubricate radius leaf anchor pin Refer to LUBRICATION SEC 0 in...

Page 241: ...eaded end of shaft c While holding shaft to prevent turning tighten nut J 8459 6 to draw bushing into the radius leaf spring eye until bushing contacts stop J 8459 2 d Check radius leaf pin for slip f...

Page 242: ...ock Nut 13 Lock Washer 14 Top Pad Slide _______________________ COM PONENTS DISASSEMBLED______________________ Figure 8 Tandem Rear Axle Suspension Hendrickson RTI Typical 15 Top Pad Bolt 16 Top Pad 1...

Page 243: ...e fram e and the suspension unit is secured by four rubber bushed drive pins one for each load cushion These bush ings perm it the drive pins to move up and down in direct relation to the movement of...

Page 244: ...5 Lower fram e to safety stands or other suitable supports INSTALLATION RT AND RU TYPE 1 Roll axles and wheels with equalizer beams and springs attached in position under fram e 2 Lower fram e as requ...

Page 245: ...l torque rods to axle brackets as described under Torque Rods 6 Connect brake lines to axles and connect prop shaft to forward rear axle as described in Propeller Shafts SEC 4D in this manual SPRING R...

Page 246: ...ure lubricant passages in pins are open 2 Insert pins into plain bushings in spring eyes and bracket and check for looseness If ex cessive looseness is evident pins and bushings must be replaced Refer...

Page 247: ...ket and spring eye with milled flat near end of pin aligned with lock bolt hole in bracket Use a soft hammer to drive pin in from outer side 4 Install spring front pin lock bolt and nut and tighten fi...

Page 248: ...attached with four nuts and special flat washers 4 Lower the cross tube and beams then slide beams from tube ends EQUALIZING BEAM INSPECTION 1 Inspect beam end bushings and beam center bushing for evi...

Page 249: ...HAFTS SEC 4D for torque rod installation and drive line angle adjustment procedure TORQUE ROD REMOVAL IMPORTANT If torque rods are to be remov ed and ends replaced or repositioned measure overall leng...

Page 250: ...ould be safely blocked to prevent rolling before starting work TANDEM UNIT REPLACEMENT TANDEM UNIT REMOVAL 1 Block wheels on both axles and disconnect brake lines from axles 2 Disconnect propeller sha...

Page 251: ...fram e ROCKER ARM PAGE AND PAGE LWH ROCKER ARM REMOVAL Fig 19 1 Safely support axles then remove wheels 2 Raise and support fram e to remove weight from rocker arm s 3 With cross tube and rocker arm s...

Page 252: ...ompression cap 2 Using a suitable tool remove rubber bush ing from trunnion mount 3 Thoroughly coat the rubber bushings trun nion mount and tube with brake fluid then insert Pedestal Spring Cap W ashe...

Page 253: ...e brackets and into rocker arm bushings 2 At each end of rocker arm install bolt with flat washer through axle bracket and rocker arm NOTE Bolt should be installed from inner side with nut located tow...

Page 254: ...remove compression washer at inside of fram e 6 Remove spring assembly from vehicle TORQUE RODS Information pertaining to torque rod removal and installation rem ains the same as covered under Torque...

Page 255: ...r bracket 6 Raise fram e until rocker arm end brackets clear ends of front and rear springs Support fram e securely 7 Remove rocker arm by pulling straight off hanger pivot pin CLEANING INSPECTION AND...

Page 256: ...st to varying loads and changing road contour The vehicle load is equalized through the leveling m easurem ents show axles to be misaligned it will be necessary to adjust alignment as follows REAR AXL...

Page 257: ...arks are used 4 File peened end of center bolt if necessary so nut can be removed Remove nut and center bolt Slowly release tension on C clamp to free spring leaves NOTE Disassembly procedure is the s...

Page 258: ...ot pounds 3 Carefully lower fram e until radius rod leaf eye is lined up with opening in spring hanger bracket 4 Insert both halves of radius leaf eye bush ing into spring hanger and radius leaf eye o...

Page 259: ...irregular and incorrect measurement could result 8 Repeat the above operation for the opposite side of axle and compare m easurem ents taken If m easurem ents are the same or vary 1 8 or less adjustme...

Page 260: ...ge flat washer from eye bolt Using a soft drift tool drive eye bolt with remaining flat washer from hanger 4 From inside of rubber bushing and using a suitable drift tool drive one half of bushing out...

Page 261: ...pen suspension oscill ations Shock absorbers are mounted at each end with replaceable two piece rubber bushings SYSTEM OPERATION Compressed air m etered into the air suspen sion system by height contr...

Page 262: ...little maintenance other than routine test and inspection Inspection and test procedures should be perform ed at established chassis inspection periods Com ponents of suspension are shown in figure 2...

Page 263: ...nction properly with the lever correctly adjusted check for air line restriction If valve still does not hold fram e at normal ride height with lever properly adjusted and with no restriction in air s...

Page 264: ...relieve pressure with in the air suspension system 3 Remove nuts from two bellows bead plate studs at fram e 4 Remove nuts from two bellows bead plate studs at bellows pedestal bracket 5 Compress bell...

Page 265: ...2 Turn cap 9 clockwise to increase pressure or counterclockwise to decrease pressure 3 Tighten lock nut 10 when correct adjust ment is obtained DISASSEMBLY NOTE Key numbers in following text refer to...

Page 266: ...d moving over travel lever out of neutral position for two seconds or more to actuate intake valve or exhaust valve Unloading When part of load is removed air pressure in bellows lifts fram e Overtrav...

Page 267: ...l Spring Large 16 Overtravel Spring Small 17 Overtravel Control Body 18 Plug Retainer 19 Lever Stud Nut 20 Overtravel Lever 21 Overtravel Lever Stud 22 Airline Fitting Gasket 23 Inlet Adapter and Chec...

Page 268: ...ssembly HEIGHT CONTROL VALVE INSTALLATION Before installing height control valve assem bly see that air line fittings are clean and undam aged Replace line connector rubber seals if de teriorated or d...

Page 269: ...rocure locally 1 Weatherhead pipe fitting 00904 104 1 W eatherhead inverted fitting 00904 B04 Vacuum Line F ittin g Sun T ester 115 3 Depth Gauge and Straightedge Procure locally Conventional Type Eye...

Page 270: ...s operation with lever in the valve body or lever may be removed and bent on the bench METHOD USING AIR PRESSURE AND VACUUM 1 If air supply and vacuum lines were not connected to valve assembly as dir...

Page 271: ...be perform ed when a vacuum source is not available 1 Connect air supply hose 80 to 110 psi to air inlet port fig 8 Figure 13 Silicone Fluid Level PRELIMINARY PROCEDURES After the valve lever gaps hav...

Page 272: ...econds first recheck the fluid level If fluid level is satisfactory the valve lever gap adjustment must be repeated step by step NOTE After obtaining proper valve adjust ments install valve cover usin...

Page 273: ...Remove overtravel control shaft 11 and overtravel control body seal 9 from body Remove shaft O rings 10 and 12 Back off vise jaw and take body and tool from vise Remove tool over travel piston 14 ove...

Page 274: ...to brace stem and pinch ends of clip just enough to secure on stem Clip must rotate freely on stem 6 Using new O ring 26 install air inlet adapter and check valve assembly 23 into valve body 7 Make a...

Page 275: ...0 T Y P E O F T O R Q U E P A G E A N D P A G E LWH P A R T F T L B S Pedestal and Spacer to Frame Lower Flange Bolt 100 120 Nut 40 50 Pedestal to Frame Bolt Vz x 20 x 2 4 4 Nut 40 50 x 18 x ZVt 1 2 N...

Page 276: ...s directed under Wheel Bearing Adjust ment following WHEEL BEARING ADJUSTMENT 1 Jack up rear axle and remove axle shaft as directed in REAR AXLES SEC 4A 2 On vehicles using outer oil seal and outer oi...

Page 277: ...Ring 25 Bolt 26 Dowel T 68J7 Figure 2 Rear Hubs and Bearings Iwith Disc Type Wheels HUB BEARING AND OIL SEAL REPLACEMENT REMOVAL Figs 2 and 3 1 Jack up rear axle and remove tire and rim assembly on ve...

Page 278: ...cribed later in this section lubricate bearings axle housing tube and inside of hub as described in LUBRICATION SEC 0 of this manual Coat lip of inner oil seal and surface contacted by lip with wheel...

Page 279: ...ent 1 To remove oil seal sleeve tap sleeve around entire circum ference with hammer to stretch the metal then use a blunt chisel to cut into the sleeve inner flange This will loosen the sleeve suffici...

Page 280: ...joint is at transm ission end of shaft if two or more shafts are used slip joint is at forward end of re a r shaft End of slip yoke is sealed by a felt or cork washer held in place by a steel washer...

Page 281: ...with auxiliary transm ission Refer to Specifications at end of this section for type of joint used at v ar ious locations on any vehicle with standard equip ment Refer to P arts Book for universal joi...

Page 282: ...t CENTER BEARING Fig 6 Center bearings are used to support center portion of drive line when two or more propeller shafts are used Bearing is ball type mounted in a rubber cushion which is attached to...

Page 283: ...ap and withdraw shaft Remove cork or felt washer steel washer and dust cap from shaft UNIVERSAL JOINT DISASSEMBLY Types 58WB and 68WB Figs 2 and 3 Remove special cap screw s and lock washers attaching...

Page 284: ...shaft splines then check splines for wear warp age and cracks If shaft is worn warped or cracked replace with new shaft Welding of broken shaft is not recommended since this operation requires special...

Page 285: ...ts except ball bearing and rubber cushion in suitable cleaning fluid DO NOT IMMERSE SEALED BEARING IN CLEANING FLUID Wipe bearing and cushion clean with a cloth dampened with cleaning fluid Check the...

Page 286: ...earing cage flanges and are used at yoke flanges which do have threaded holes 1 Install bearing assem blies over opposite ends of journals and position against yoke flange Make sure lug on bearing cag...

Page 287: ...REAR SUSPENSION 4 74 TPM 9995 Figure 7 Checking Drive Line Angles CHEVROLET SERIES 70 90 HEAVY DUTY TRUCK SHOP MANUAL...

Page 288: ...at both ends of each cross beam must be equal Make adjustments as necessary If adjustment is made it is mandatory to recheck the auxiliary transm ission angle as described in step 3 5 Check angle of...

Page 289: ...t angle of the inter axle shaft angle subtracted from the rear axle pinion angle Refer to figure 9 for location of shim s Example Forward axle pinion angle 3 In t e r a x l e shaft angle 6 Rear axle p...

Page 290: ...0 1700 1700 FC 9 0 1800 1800 1800 1800 FH 9 0 1800 1800 1800 1800 FI9 0 68W B 68WB 68WB 68WB FN 9 0 68WB 68WB 68WB 68W B DC90 1800 1800 1800 1800 1700 1700 D H 9 0 1800 1800 1800 1800 1700 1700 DI90 1...

Page 291: ...n g e b o l t s a n d u n i v e r s a l j o i n t U b o l t s s h o u l d b e m a i n t a i n e d t o p r e v e n t v i b r a t i o n a n d d a m a g e t o n e e d l e b e a r i n g s a n d m o u n t...

Page 292: ...t e r s m a i n c y l i n d e r s w h e e l c y l i n d e r s l i n e s g a u g e s r e s e r v e t a n k s e t c a r e c o v e r e d u n d e r r e s p e c t i v e h e a d i n g s i n t h i s s e c t...

Page 293: ...h w r e n c h 3 P l a c e w r e n c h o n o p p o s i t e a d j u s t i n g c a m s t u d a n d a d j u s t s e c o n d s h o e b y r e p e a t i n g s t e p s 1 a n d 2 T Y P E F R 3 F i g 3 1 J a c...

Page 294: ...t b r a k e s y s t e m b e b l e d i n a d e f i n i t e s e q u e n c e t o o b t a i n b e s t r e s u l t s F i g u r e s 4 a n d 5 i l l u s t r a t e v a r i o u s c o m b i n a t i o n s o f b...

Page 295: ...e r o p e r a t i o n o f e i t h e r o r b o t h o f t h e s e v a l v e s w i l l r e s u l t i n t h e s a m e p e d a l f e e l a s a i r i n t h e s y s t e m R e f e r t o a p p l i c a b l e p...

Page 296: ...d a l t h e c l u t c h p e d a l m u s t a l s o b e r e m o v e d 1 R e m o v e b o l t s a t t a c h i n g b r a k e a n d c l u t c h m a s t e r c y l i n d e r p u s h r o d s t o p e d a l l e...

Page 297: ...i t t i n g f r o m b u s h i n g 7 R e m o v e b o l t s w h i c h f a s t e n b u s h i n g a s s e m b l y t o c a b s i l l 8 S i m u l t a n e o u s l y s l i d e p e d a l a s s e m b l y a n d...

Page 298: ...t i t u t e d e s i g n T o r q u e v a l u e s m u s t b e u s e d a s s p e c i f i e d d u r i n g r e a s s e m b l y t o a s s u r e p r o p e r r e t e n t i o n o f t h i s p a r t C O N V E N...

Page 299: ...s c r e w w h e r e u s e d C l e a n i n g I m m e r s e a l l p a r t s i n d e n a t u r e d a l c o h o l a n d w a s h t h o r o u g h l y W i p e s m a l l p a r t s d r y a n d b l o w o u t i...

Page 300: ...e r b o r e w i t h l i p o f c u p t o w a r d o u t l e t e n d M a k e s u r e e n d o f s p r i n g s e a t s i n s i d e t h e c u p c I n s e r t p i s t o n a n d s e c o n d a r y c u p i n t...

Page 301: ...e c t r i c a l l e a d f r o m p r e s s u r e d i f f e r e n t i a l s w i t c h 3 P l a c e d r y r a g s b e l o w t h e s w i t c h t o a b s o r b a n y f l u i d s p i l l e d d u r i n g r e...

Page 302: ...n d t w o s m a l l b o l t s a t t a c h i n g e a c h c y l i n d e r t o b a c k i n g p l a t e t h e n r e m o v e c y l i n d e r s f r o m b a c k i n g p l a t e I n s t a l l a t i o n N O T...

Page 303: ...d o u t r e p l a c e c y l i n d e r 3 C h e c k f i t o f n e w p i s t o n s i n c y l i n d e r b o r e u s i n g a f e e l e r g a u g e s e e f i g 1 1 C l e a r a n c e s h o u l d b e w i t h...

Page 304: ...h r e a d e d i n t o a x l e t e e w i t h a c o p p e r g a s k e t u s e d t o s e a l t h e c o n n e c t i o n O t h e r e n d o f h o s e i s i n s e r t e d t h r o u g h f r a m e b r a c k e...

Page 305: ...l i n e s f o r l e a k a g e a n d f o r r e s t r i c t i o n c a u s e d b y b e n t o r k i n k e d t u b e o r h o s e I f n o f a u l t i s f o u n d i n l i n e s t r o u b l e i s i n p o w e...

Page 306: ...t e n g i n e a n d t e s t o p e r a t i o n o f b r a k e s y s t e m a s d i r e c t e d R e f e r t o T r o u b l e s h o o t i n g C h a r t i n t h i s s e c t i o n i f o p e r a t i o n i s n...

Page 307: ...s i m p r o p e r l y i t m u s t b e r e p l a c e d G a u g e s d i f f e r i n s i z e a p p e a r a n c e a n d c o l o r d e p e n d e n t u p o n t r u c k m o d e l A l l a r e l o c a t e d i...

Page 308: ...t h r o u g h h o l e i n s h o e w e b l o c a t e t o e i n w h e e l c y l i n d e r p i s t o n s h o e g u i d e a n d p o s i t i o n h e e l i n s l o t i n a n c h o r b l o c k 3 I n s t a l...

Page 309: ...S h o e R e l i n i n g i n t h i s s e c t i o n 7 I n s p e c t b a c k i n g p l a t e f o r c r a c k s o r d i s t o r t i o n R e p l a c e i f d e f e c t i v e B R A K E S H O E I N S T A L L...

Page 310: ...nst the friction ring on the star wheel screw this may damage the friction ring 2 U n h o o k t h e t w o a u t o m a t i c a d j u s t e r s p r i n g s 3 R e m o v e t h e t w o l o n g c r a n k l...

Page 311: ...o n o f w e b l o c a t e d i n t h e a d j u s t e r s l o t a n d t h e h e e l i n t h e a n c h o r p i n s l o t o f a n c h o r s u p p o r t s 3 I n s t a l l b r a k e s h o e h o l d d o w n...

Page 312: ...l o t c o v e r s A u t o m a t i c a d j u s t m e n t n o w t a k e s o v e r BRAKE SHOE RELINING B r a k e l i n i n g s o n m o s t m o d e l s a r e r i v e t e d t o t h e b r a k e s h o e s a...

Page 313: ...t e r c y l i n d e r f i l l e r v e n t c l o g g e d 6 W e a k h o s e 1 R e m o v e a i r b y b l e e d i n g 2 F l u s h r e f i l l a n d b l e e d s y s t e m U s e r e c o m m e n d e d b r a...

Page 314: ...w o l l e n c u p i n m a s t e r c y l i n d e r 3 M a s t e r c y l i n d e r p i s t o n n o t r e t u r n i n g 4 W e a k s h o e r e t r a c t i n g s p r i n g s 5 W h e e l c y l i n d e r p i...

Page 315: ...b o t h f r o n t o r r e a r d r u m s 7 C l e a n o u t o r r e p l a c e 8 R e p l a c e 9 R e p l a c e w i t h s p e c i f i e d l i n i n g R E A R B R A K E S D R A G R E M E D Y P R O B A B L...

Page 316: ...m s i d e t o s i d e W E T W E A T H E R B R A K E S G R A B O R W O N T H O L D R E M E D Y P R O B A B L E C A U S E 1 L i n i n g s t o o s e n s i t i v e t o w a t e r 2 D i r t y b r a k e s 3...

Page 317: ...n d a r d h y d r a u l i c b r a k e s A f t e r t h e s e p o s s i b l e c a u s e s h a v e b e e n e l i m i n a t e d c h e c k f o r c a u s e a s o u t l i n e d b e l o w N O T E M a k e t h...

Page 318: ...i o n 3 B r o k e n r e t u r n s p r i n g 1 R e b u i l d u n i t 2 R e b u i l d u n i t 3 R e p l a c e s p r i n g B R A K E S G R A B B Y R E M E D Y P R O B A B L E C A U S E 1 B r o k e n v a...

Page 319: ...a Sq In per axle F R 3 Manual 1 5 x 7 7 W 440 0 FR 3 Manual 15 x 6 6 W 379 6 BRAKE CONTROLS TRUCK SERIES H70 T70 170 Wheel Cylinder Bore Master Cylinder Bore F r o n t Rear l s PA M W i P 4 1 lVt m P...

Page 320: ...o n t r o l s e t c c o v e r e d i n t h i s m a n u a l a p p l y t o b o t h c a m t y p e a n d S t o p m a s t e r t y p e b r a k e s y s t e m s BRAKE SYSTEM MAINTENANCE N o r m a l o p e r a...

Page 321: ...w i t c h 5 L i n e t o T r a c t o r P r o t e c t i o n V a l v e 6 P e d a l S t o p B u t t o n P e d a l A s s e m b l y 8 P e d a l t o V a l v e B o l t s V a l v e A s s e m b l y T 2 1 2 6 e...

Page 322: ...7583 P E D A L S T O P S C R E W A D J U S T M E N T T I L T C A B M O D E L S F i g 3 P e d a l s t o p s c r e w a d j u s t m e n t c o n t r o l s t h e e x h a u s t o p e n i n g b e t w e e n t...

Page 323: ...m b r a k e s w i l l b e o b t a i n e d w h e n t h e a r m t r a v e l o f t h e s l a c k a d j u s t e r i s h e l d t o a m i n i m u m s o t h a t 4 PU SH LO C K S L E E V E IN TO DISENGAGE H...

Page 324: ...o u n t i n g B r a c k e t 4 S l a c k A d j u s t e r 5 R e a r A x l e 9 10 S n a p R i n g B r a k e C a m s h a f t L u b r i c a t i o n H o l e P lu g C l e v i s p i n A d j u s t i n g C l e...

Page 325: ...H A M B E R S E R V I C E A B I L I T Y T E S T S 1 O p e r a t i n g T e s t A p p l y b r a k e s a n d s e e t h a t t h e b r a k e c h a m b e r p u s h r o d s m o v e o u t p r o m p t l y w i...

Page 326: ...a r g e d f r o m t h e c o m p r e s s o r C o n d e n s a t i o n s h o u l d b e d r a i n e d f r o m a l l a i r t a n k s d a i l y T o d r a i n t a n k s p r o p e r l y l e a v e d r a i n c...

Page 327: ...b e d i s a s s e m b l e d c l e a n e d w i t h k e r o s e n e a n d r e s e t t o b l o w o f f a t 1 4 5 t o 1 5 5 p o u n d s p r e s s u r e A D J U S T M E N T F i g 1 3 1 L o o s e n l o c k...

Page 328: ...e l e a s e t h e b r a k e s b y h a s t e n i n g t h e e x h a u s t o f a i r p r e s s u r e f r o m t h e b r a k e c h a m b e r s T h e v a l v e c o n s i s t s o f a b o d y c o v e r a n d...

Page 329: ...t h o n e b o l t t o f a s t e n a p p l i c a t i o n v a l v e s e c u r e l y t o c o w l A p e d a l b r a c k e t a n d p e d a l a s s e m b l y i s f a s t e n e d t o t h e b o t t o m o f t...

Page 330: ...r o m v a l v e 5 D i s c o n n e c t e x h a u s t h o s e f r o m v a l v e e x h a u s t p o r t 6 R e m o v e b o l t s w h i c h a t t a c h s u p p o r t b r a c k e t t o c a b a n d r e m o v...

Page 331: ...g p i s t o n s e a l s PREVENTIVE MAINTENANCE B R A K E P E D A L N o r e g u l a r p e r i o d i c m a i n t e n a n c e i s r e q u i r e d A t t h e t i m e o f e a c h c h a s s i s l u b r i c...

Page 332: ...o n I f t h i s f a i l s t o c o r r e c t T r a i l e r H o s e C o u p l i n g s 2 D u m m y C o u p l i n g s 3 B r a k e a n d E l e c t r i c a l L i n e s H o s e S u p p o r t S p r i n g s E...

Page 333: ...t h a n a c c u r a t e t e s t g a u g e I f p r e s s u r e r e a d i n g v a r i e s 4 p o u n d s o r m o r e r e p l a c e g a u g e w i t h a r e c a l i b r a t e d u n i t LOW AIR PRESSURE SWI...

Page 334: ...e w i l l c o n t r o l t h e b r a k e s O n s o m e v a l v e s i t i s n e c e s s a r y t o h o l d t h e h a n d l e i n t h e d e s i r e d p o s i t i o n i n o r d e r t o a p p l y t r a i l...

Page 335: ...M IS NOT DESIGNED TO BE USED AS A PARKING BRAKE UNDER ANY CIRCUMSTANCES T h e r e a r e s e v e r a l d i f f e r e n t m o d e l c o n t r o l v a l v e s u s e d o n t h e s e v e h i c l e s b u t...

Page 336: ...2 E x h a u s t a i r f r o m b r a k e s y s t e m 3 R e m o v e l a r g e c i r c u i t b r e a k e r a c c e s s c o v e r f r o m b e h i n d i n s t r u m e n t p a n e l 4 D i s c o n n e c t a...

Page 337: ...n s t r u m e n t p a n e l 2 C o n n e c t a i r l i n e s 3 P u s h v a l v e s h a f t u p t h r o u g h c o n t r o l p a n e l a n d i n s t a l l n u t a n d k n o b o n v a l v e s h a f t 4 B...

Page 338: ...r e c o n n e c t e d t o t h e f r o n t b r a k e c h a m b e r s t h e s e s w i t c h e s i s t o l i g h t t h e s t o p l i g h t s t o w a r n f o l l o w i n g d r i v e r s o f b r a k e a p...

Page 339: ...t Application V a lve _____ d Air Tank Exhaust Port Plunger DRY ROAD POSITION Limiting Quick Release Valve Inlet Valve Valve Carrier Front Brake Chambers SLIPPERY ROAD POSITION TPM 6583 Figure 19 Fron...

Page 340: ...f t h i s m a n u a l I n s t a l l a t i o n 1 P o s i t i o n v a l v e i n i n s t r u m e n t p a n e l a n d c o n n e c t a i r l i n e s 2 F a s t e n v a l v e a n d p l a t e t o i n s t r u...

Page 341: ...i n t h i s s e c t i o n M a x i m u m b r a k i n g e f f i c i e n c y c a n b e o b t a i n e d i m m e d i a t e l y i f l i n i n g s a r e t r u e d u p w i t h a c o n v e n t i o n a l l i n...

Page 342: ...i e s a r e u s e d o n r e a r a x l e o f a l l s t e e l t i l t c a b m o d e l s A l l c o n v e n t i o n a l c a b m o d e l s a n d A l u m T i l t m o d e l s u s e S t o p m a s t e r b r a...

Page 343: ...d i n r e l a t i o n t o c e n t e r o f h u b W h e n e v e r a n y p a r t o f t h e b r a k e a s s e m b l y h a s b e e n r e m o v e d a n d r e p l a c e d a d j u s t b r a k e s a s d i r e...

Page 344: ...l o p i n g s i d e s o f t h e t e e t h o n t h e a c t u a t o r I f t h e p l u n g e r a s s e m b l y m o v e s o u t w a r d a n d e x c e e d s t h e p i t c h d i s t a n c e t h e t e e t h...

Page 345: ...e m o v e b r a k e s h o e s a n d b r a k e c h a m b e r s a s d e t a i l e d u n d e r a p p l i c a b l e p r o c e d u r e s 2 R e m o v e b o l t a n d p l u n g e r g u i d e g a s k e t f r...

Page 346: ...n d t h o r o u g h l y c l e a n e d a t t h e t i m e t h a t b r a k e s a r e r e l i n e d o r a t o n e y e a r p e r i o d s w h i c h e v e r o c c u r s f i r s t a l s o d e p e n d e n t u...

Page 347: ...t e n i n g t h e c o l l e t n u t a g a i n s t l o c k w a s h e r a n d t h e s p i d e r h o u s i n g s e e f i g 2 9 D r i v e c o l l e t n u t t i g h t w i t h a d r i f t a n d h a m m e r...

Page 348: ...Shoe Hold Down Clip 13 Guide Screw 14 Anchor Plunger Solid 15 Brake Shoe Return Spring 16 Dust Shield 17 Lock Washer 18 Bolt 19 Dust Cover 20 Wedge Shaft 21 Roller 22 Roller Retaining Cage 23 Wedge Sp...

Page 349: ...s might indicate faulty internal part or parts which would not necessitate brake chamber disassem bly or new brake lining Actuation components should then be inspected for faulty or unacceptable con d...

Page 350: ...f there is evidence of wear or distortion 2 Examine rollers for any wear or out of round condition No scratches or scoring is per m issible 3 Examine wedge spring for fatigue or cor rosion Replace spr...

Page 351: ...er a s sembly consists of an inner and outer chamber The inner chamber containing a diaphragm and diaphragm plate rod serves as the service brake chamber and operates in the same manner as a conventio...

Page 352: ...any grade on which vehicle is expected to operate Release the brakes by pushing knob in Brakes should re lease instantly and wheels turn freely LEAKAGE TEST 1 Service Brakes With brakes applied check...

Page 353: ...ED Figure 39 Compressing Fail Safe Power Spring 1 With air pressure in parking brake cham ber brake released loosen release bolt spring lock and swing to one side then turn release bolt clockwise as f...

Page 354: ...ssemble the cap and spring assembly In the event any part of this assembly is de fective the complete assembly must be Replaced The component parts are not serviced separately CLEANING AND INSPECTION...

Page 355: ...hex end of cap 4 Position diaphragm over plate rod then in stall pressure housing and cap assem bly NOTE Diaphragm should fit evenly between pressure housing and non pressure housing Align marks made...

Page 356: ...re Nut 17 Hex Nut 18 Piston 19 Diaphragm 20 Push Rod Figure 44 Super Fail Safe Assembly SERVICE RECOMMENDATIONS CAGING AND UNCAGING POWER SPRING On the Super Fail Safe the head of the re lease bolt is...

Page 357: ...move O ring and outer washer from release bolt 20 Remove filter from cap IMPORTANT DO NOT remove breather a s sembly from cap unless inspection indicates dam age It is necessary to cut the nail to rem...

Page 358: ...spring will apply the brakes Application will be gin when pressure drops to approximately 45 psi and will be complete when pressure reaches ap proximately 25 psi MANUAL RELEASE In the event of an auto...

Page 359: ...h rod clevis from slack ad juster 6 Remove nuts and lock washers from mount ing studs 7 Remove Anchorlok brake chamber from mounting bracket Installation 1 Place Anchorlok chamber in position on mount...

Page 360: ...of adjustment 5 Adjust 6 Wrong size brake chambers 6 Replace according to Specifications SLOW BRAKE APPLICATION REMEDY PROBABLE CAUSE 1 Low brake line pressure 2 Linkage binding 3 Too much push rod tr...

Page 361: ...EMEDY PROBABLE CAUSE 1 Uneven slack adjuster settings 2 Linkage binding at one or more wheels 3 Linings worn uneven 4 Brake shoe return spring weak or broken 5 Defective brake chamber 6 Defective brak...

Page 362: ...e 3 Repair or replace 4 Repair or replace 5 Close repair or replace BRAKES FULLY APPLIED 1 Leaking brake chamber 2 Leaking application valve 3 Leaking service line 4 Leaking chamber hoses 5 Dirt in tw...

Page 363: ...rs or piston stuck in cap 4 Fail Safe spring failure 5 Rollers not aligned with plungers or wedge not mated with diaphragm plate rod 6 Brakes out of adjustment 1 Turn release bolt counterclockwise 2 C...

Page 364: ...brake shoe adjustment 4 Improper wedge adjustment 5 Plunger seal failure 6 Grease on linings 1 Check system for leaks 2 Replace diaphragm 3 Adjust brake shoes 4 Make wedge adjustment 5 Replace seal a...

Page 365: ...Area sq in per axle 377 440 Brake Chamber Type 30 30 Diameter 8Vs S V b Adjust Travel to Short as possible without brakes dragging Slack Adjuster Type PL 24 PL 24 Length Between H ole Centers 51 2 6 S...

Page 366: ...en upper end of lining and drum Measure clearance about 3 inches from end of lining Tighten lock nut on adjusting bolt 5 Adjust end on brake rod so that clevis pin may be freely inserted through opera...

Page 367: ...output shaft flange clean Position brake drum on flange and press serrated bolts into place Replace drum assem bly and retaining nut on output shaft See Specifications in TRANSMISSION ON VE HICLE SERV...

Page 368: ...heads Rivet new lining securely and evenly on shoes 3 Inspect two shoe return springs and adjust ing screw spring Parts damaged or worn should be replaced with new parts BRAKE SHOE INSTALLATION Fig 3...

Page 369: ...rts enough pressure to bring lever against front lever arm 3 Insert a 1 32 shim between rear shoe lin ing and brake disc 4 Tighten adjusting nut until front shoe lining is firm ly against disc yet sti...

Page 370: ...ver in OFF position 2 Adjust clevis and nut to provide for free pin at brake lever 3 Pull brake lever to ON position Check for brake holding ability 4 Readjust if necessary STOPMASTER FAIL SAFE BRAKES...

Page 371: ...um Diameter Lining Length approx LiningWidth LiningThickness Total Lining Area Sq In 914 x 2 4 914 27 IW 3 l6 67 5 91 4 x 3 914 27 3 Ms 81 0 1 014 x 3 1014 3 3 1 3 2 3 5 l6 99 1 1 114 x 314 WW 36 314...

Page 372: ...ous items and tuning the en gine Unless otherwise stated the procedures are applicable to all gasoline engines used in vehicles covered by this section To adequately accomplish a satisfactory tune up...

Page 373: ...om Camshaft Rear Bearing 8 Rocker Arms 9 Oil Drain Back Holes 10 Oil Filter 11 Oil Pump Inlet Screen 12 Oil Pump 13 Piston Pin Splash Lubricated 14 Timing Idler Gear Shaft 15 Cylinder Block 16 Balance...

Page 374: ...ilter element as an assem bly Remove housing gasket 2 Remove element from housing and discard elem ent Clean housing thoroughly Also clean filter bracket 3 Install new element in housing shell and pos...

Page 375: ...ossible reading 3 Make compression check at each cylinder and record each reading 4 If som e cylinders have low compression inject about one tablespoon of engine oil into com bustion chamber through s...

Page 376: ...king check of cranking voltage it is noted that cranking speed is uneven this is indication of uneven com pression defective starter or starter drive 4 In cases where loose corroded or other w ise def...

Page 377: ...ck ignition timing with timing light Loosen distrib utor clamp and rotate distributor body to change timing as required Tighten distributor clamp and connect vacuum line after checking timing 4 While...

Page 378: ...emove hose from breather cap on rocker arm cover and check for obstructions in hose 6 fig 5 Remove breather cap 3 fig 5 Inspect IMPORTANT NOTE The positive crankcase ventilation P C V valve s MUST be...

Page 379: ...hood 4 Remove grille and radiator braces 5 Remove radiator and heater hoses 6 Disconnect oil cooler lines from radiator some engines do not have oil cooler 7 Remove grille and radiator Also remove fr...

Page 380: ...ve lifters cannot be removed until from draining from clutch control system while engine is removed 9 Disconnect parking brake control except when air operated brake is used and speedometer drive at r...

Page 381: ...at rocker arm s Lift off the rocker arm shaft and brackets with attaching bolts as an assem bly 3 Remove push rods and identify in some manner so they can be returned to original posi tion at assem b...

Page 382: ...ter J 21546 in spark plug hole 3 Remove the rocker arm shaft and bracket assem bly from cylinder head Install a 3 8 16 stud in bracket bolt hole adjacent to the valve spring to be removed Stud must ha...

Page 383: ...ll valve rocker arm cover and gasket MANIFOLD REPLACEMENT EXHAUST MANIFOLDS ALL ENGINES 1 Disconnect exhaust pipe from exhaust manifold 2 Bend locks away from manifold attaching bolts then remove bolt...

Page 384: ...face on cylinder head and on cylinder block Surfaces must be clean Place cylinder head gasket on top of cylinder block with word TOP facing upwards Dowels will locate gasket If available guide pins fi...

Page 385: ...coated bolt is used tighten bolt to 180 200 foot pounds torque If cadmium plated bolt is used correct torque is 240 to 260 foot pounds CRANKSHAFT FRONT OIL SEAL REPLACEMENT REMOVAL 1 Remove crankshaft...

Page 386: ...se must be installed at rear of oil pan at reinforcement These bolts may be readily identified by internal external type lock w ashers Other pan bolts are shorter 3 Install drain plug with new gasket...

Page 387: ...in position at cyl inder block and turn pump as necessary to engage pump drive shaft with drive socket at upper end 3 Position the hydraulic governor line 2 fig 17 at fittings on cylinder block and o...

Page 388: ...bolts is 6 to 8 foot pounds 4 Install drain plug with new gasket then fill crankcase with engine oil to FULL mark on dip stick Use oil as specified in LUBRICATION SEC 0 in this manual TACHOMETER DRIV...

Page 389: ...sharp bends or kinks in the assem bly Lubricate tachometer drive cable with approved lubricant Type ST 640 or equivalent HYDRAULIC GOVERNOR TROUBLESHOOTING To check for proper performance of hydraulic...

Page 390: ...ifold Bolts V8 Eng 25 30 Damper or Hub to Crankshaft Bolt Exhaust Manifold Bolts 15 20 Phosphate Coated B o lt 180 200 Water Outlet Manifold Bolts V6 Eng 20 25 Cadmium Plated Bolt 240 260 Oil Filter S...

Page 391: ...ly 2 Check amount of fuel in tank fill if supply is low 3 Clogged vent in fuel tank cap 3 Clean or replace cap 4 Break in fuel supply line allowing air to be drawn into fuel line 4 Replace or repair l...

Page 392: ...M B IGNITION SYSTEM MALFUNCTION REMEDY 1 Set ignition timing 2 Clean or replace spark plugs 3 Clean and adjust points or replace POSSIBLE CAUSES 1 Ignition out of tim e 2 Defective spark plugs 3 Distr...

Page 393: ...necessary 4 Partially clogged radiator 4 Clean radiator core internal passages and air passages 5 Defective water pump 5 Repair or replace pump 6 Incorrect ignition or valve timing 6 Retime engine 7 D...

Page 394: ...e too far for fuel being used 2 Wrong type heat range spark plug 3 Excessive build up of deposits in combustion chambers 4 Restricted coolant passages in cylinder head causing hot spots in combustion...

Page 395: ...ine and correct cause of push rod bend ing Install new push rod 4 Replace worn parts and make sure oil is reach ing valve rocker arms 5 Replace spring 6 Replace lifter and or camshaft SYMPTOM B BEARIN...

Page 396: ...nance program Be sure all bracket attaching bolts are kept tight Refer to ENGINE MOUNTINGS SEC 6D for engine mounting information USE ENGINE OIL AS SPECIFIED IN LUBRICATION SEC 0 AND SERVICE CRANKCASE...

Page 397: ......

Page 398: ...he engine IMPORTANT IN DUST STORM AREAS AIR CLEANERS MUST BE SERVICED IMMEDIATELY AFTER SUCH STORMS OCCUR WARNING USE EXTREME CAUTION TO BE SURE ALL VOLATILE CLEANINGFLUID GASOLINE KEROSENE ETC IS RE...

Page 399: ...ES If battery is weak or shows other evidence of being defective refer to appropriate coverage in ENGINE ELECTRICAL SEC 6Y of this manual for method of diagnosing battery deficiencies CHARGING CIRCUIT...

Page 400: ...ck valve clearance with gauge J 9708 after the engine has reached its normal operating temperature All valve clearances can be adjusted during one full revolution of the crankshaft Cylinder numbers ar...

Page 401: ...push rod lock nut 5 Turn the push rod until the extended part of the gauge will just pass over the top of the in jector follower guide fig 3 NOTE Turning or spinning the timing gauge lightly with the...

Page 402: ...ck out the buffer screw until it extends 9 16 to 5 8 from the surface of the governor housing This is to prevent interference with dif ferential lever while adjusting governor gap and setting injector...

Page 403: ...control tube lever is observed or a step up in effort to turn the screwdriver is noted This will place rear No 3L fig 2 injector in the full fuel position Turn down the outer adjusting screw until it...

Page 404: ...er covers ADJUST MAXIMUM NO LOAD ENGINE SPEED All governors are properly adjusted before leaving the factory However if the governor has been reconditioned or replaced and to ensure the engine speed w...

Page 405: ...off to steady idle speed If engine rolls or surges more than two tim es the buffer screw needs to be adjusted slightly in If the engine does not roll or surge one to two tim es the screw is in too fa...

Page 406: ...ump and lines to remain on chassis 10 Disconnect exhaust pipes from manifold Disconnect fuel supply and return lines 11 Disconnect oil cooler lines from fittings at radiator lower tank Also disconnect...

Page 407: ...te the components INSTALLATION Refer to applicable portion of TRANSMIS SIONS AND CLUTCHES SEC 7 of this manual for information required to properly assem ble clutch parts and transm ission to engine 1...

Page 408: ...or left hand cylinder bank may be re placed in manner described below REMOVAL 1 Drain cooling system Remove engine ac cess cover from inside cab fig 12 2 Disconnect battery to prevent damage from acc...

Page 409: ...Fig 17 1 Inspect top of pistons to see that they are clean and free from carbon deposits Also check and if necessary remove any deposits found in groove and counterbores in top of cylinder block 2 Ins...

Page 410: ...using on front of cylinder head 13 Use new gasket and install exhaust mani fold Tighten manifold stud nuts to 25 to 40 foot pounds 14 Connect exhaust pipe Fill cooling system and check for leaks 15 Re...

Page 411: ...er IMPORTANT Be careful not to damage the seal surface on crankshaft INSTALLATION 1 Carefully clean any old sealant from bore in front cover 2 Apply thin coat of sealant to outer diameter of new seal...

Page 412: ...oil cooler by pass valve is located on the right side of the engine front cover and the oil pressure regulator valve is located on the left side as viewed from the rear of the engine If oil cooler be...

Page 413: ...tion Chart below shows standard and optional engines for each truck model ENGINE MAINTENANCE Recommendations given under corresponding heading on page 419 in previous section on 6V 53 DIESEL ENGINES i...

Page 414: ...injector plunger may bottom before being properly adjusted Clearance between exhaust valve stem and bridge with engine at operating temperature is important and should be maintained Too little cleara...

Page 415: ...lashed in firing order se quence during one full revolution of the crankshaft Figure 3 Cylinder Numbering and Firing Order In Line 6 Cylinder Engine RIGHT BANK r n FRONT O LEFT BANK ____ FIRING ORDER...

Page 416: ...d direction of rotation as the bolt w ill be loosened 3 The injector is identified by a colored tab stamped onto the injector body Injector is timed with gauge listed in chart following 4 Place the in...

Page 417: ...injec tor control rack Ordinarily this adjustment is necessary only when governor assem bly is repair ed or replaced When necessary to check or adjust proceed as follows The following tune up adjustm...

Page 418: ...not prop erly installed there will be no control of the engine and serious damage can occur POSITION INJECTOR RACK CONTROL LEVERS The position of the injector racks must be correctly set in relation...

Page 419: ...the injector control rack fig 12 when the speed control lever is moved to the maximum speed position 2 Hold the speed control lever in the max imum speed position and using a screw driver or finger ti...

Page 420: ...he sam e tension on the ball end of their respective rack control levers when checked with screwdriver or fingers figs 12 and 13 j Recheck the No 2 and No 1 injector rack couplings on In line engine w...

Page 421: ...l brake Switch at the governor in order to make buffer screw adjustment refer to Engine Brake later in this section With the idle speed set the buffer screw may be adjusted as follows 1 With the engin...

Page 422: ...d on the serial number pad of the cylinder block When checking or setting these injectors use timing tool J 1242 with 1 484 dimension instead of J 1853 as used on all other injectors Note 1 No load go...

Page 423: ...r o u n d s t r a p f r o m s t a r t e r 3 D i s c o n n e c t w i r i n g a t t e r m i n a l s a n d m u l t i p l e w i r e c o n n e c t o r s o n c a b 4 D r a i n c o o l i n g s y s t e m D i...

Page 424: ...i c l e i s e q u i p p e d w i t h a u x i l i a r y t r a n s m i s s i o n r e m o v e t o w e r a n d l e v e r f r o m i n s i d e c a b 1 2 D i s c o n n e c t p r o p e l l e r s h a f t a n d...

Page 425: ...h overhead lifting equipment and raise power plant assem bly Check all lines wir ing or controls to be sure all have been discon nected then remove power plant 23 If it is necessary to remove transm i...

Page 426: ...and engine trim item s on engine referring to appropriate sections in this manual for necessary instructions Figure 19 shows view of engine installation with typical accessories 2 Install the power p...

Page 427: ...IJ 74S5I for Replacing Valve Spring with Cylinder Head Installed cap valve spring and spring seat 10 Reassem ble spring seat spring and spring cap then use tool in sam e manner as described for remova...

Page 428: ...and remove bolts attaching gov ernor drive housing to blower housing Remove governor housing from engine 10 Remove exhaust manifold and water outlet manifold from cylinder head NOTE If head is to be r...

Page 429: ...the cam fol lower springs After head is squarely seated use a torque wrench to tighten nuts and bolts in s e quence shown in figure 23 Tighten each nut and bolt about one half turn at a tim e until a...

Page 430: ...and fuel connectors to prevent entrance of dirt 11 Loosen rocker arm bracket bolts to re lieve valve spring pressure and cam follower 12 Remove bolts attaching thermostat hous ing to front of cylinde...

Page 431: ...tall governor housing cover Be sure fuel rod cover hose is moved into place and clamped in position 12 Bolt thermostat housing to front of cylin der head using new gasket Connect all radiator hoses an...

Page 432: ...from crankshaft Remove pulley keys from crank shaft 4 Remove vibration damper and hub using tool J 4794 01 as shown in figure 27 Install pul ley retaining bolt in threaded hole in crankshaft to provid...

Page 433: ...eal without removing front cover from engine REMOVAL 1 Remove fan if crankshaft mounted pulley and damper on In line engines Refer to proced ure previously given under Vibration Damper Front Cover and...

Page 434: ...e is le ss than three pounds the switch points are closed If circuit is energized by turning on the engine control switch the Low Oil tell tale light illum inates and warning buzzer sounds Whenever oi...

Page 435: ...is forced upward By releasing the com pressed air from cylinder at top of piston stroke at all cylinders a constant brak ing action takes place whenever foot is removed from accelerator As accelerato...

Page 436: ...V type engines however on In line engines two supply housings are used and each one is connected to a pair of drone hous ings fig 31 Two supply housings and two drone housings are used at each bank o...

Page 437: ...ad 2 Disconnect solenoid w ires from feed wire term inals 3 Loosen lock nut on oil connector s then use wrench fig 35 to turn the connector into the drone unit far enough to permit removal of either h...

Page 438: ...5 Install oil connector screw and lock nut Figure 36 Installing Oil Connector in Housing IPrior to Housing Installation fig 36 in drone housing assem bly Screw must be installed far enough to avoid in...

Page 439: ...I8V 71 Engine Shown Figure 40 Adjusting Slave Piston Clearance screw and tighten lock nut NOTE The foregoing adjustment must be made at each slave piston 14 Turn on engine control switch and engine br...

Page 440: ...firmly BUFFER SCREW SWITCH REMOVAL 1 Disconnect w ires from switch term inals 6 fig 42 j SPECIAL BUFFER SCREW SWJTCH BRACKET ATTACHING NUT Figure 44 Buffer Screw Installation 2 Use two wrenches in ma...

Page 441: ...tion to actuating rod fig 45 NOTE A 12 volt test light may be used to determine when switch is actuated The control switch must be turned on to supply current to switch feed wire during test ENGINE BR...

Page 442: ...f necessary 4 Readjust or replace switch Check for proper operation of throttle and clutch return springs One or More Cylinders Fail to Stop Braking or Engine Stalls 1 One or more slave piston control...

Page 443: ...be tightened while bridge is installed in engine Hold Bridge in Vise When tightening Nut Engine Brake Hold down Bolts Fuel Line Nut 20 25 Ft Lbs 88 92 Ft Lbs 12 15 Ft Lbs 15 18 Ft Lbs Slave Piston Adj...

Page 444: ...ler unit an oil fil ter and pressure relief valves as shown Oil pump output pressure is controlled by pressure regula tor valve in oil pump body Inlet to oil pump is through a fixed type inlet screen...

Page 445: ...kshaft B o l t 290 310 Oil Filter Center Bolt 40 50 Oil Pan Drain Plug 35 40 Lifting Bracket Bolts In Line E n g in e 55 60 Rack Control Tube Bracket B o lt s 10 12 Front Cover Bolts 3 8 24 25 30 1 2...

Page 446: ...termining cause of such conditions are covered on the following pages SATISFACTORY ENGINE OPERATION DEPENDS PRIMARILY ON 1 The presence of an adequate supply of air com pressed to a sufficiently high...

Page 447: ...ing motor to check the com pression pressure Compression pressure is affected by altitude as follows Figure 2 Checking Compression Pressure ITypical Min Compression Pressure Psi Altitude Feet 53 Seri...

Page 448: ...m the return line per minute 3 Be sure all line connections between the fuel supply and the pump are tight so no air will be drawn into the fuel system then im m erse the end of the fuel return line i...

Page 449: ...loose piston pin retainers worn blower oil seals defec tive blower cylinder head or end plate gaskets or excessive exhaust back pressure Also the breather tube or crankcase ventilator should be checke...

Page 450: ...w as possible considering the size and capacity of the air cleaner An obstruction in the air inlet system or dirty or damaged air cleaners will result in a high blower inlet restriction The air inlet...

Page 451: ...s shape Water wets the surface and therefore has a concave men iscus A mercury column is read by sighting hor izontally between the top of the convex mercury surface fig 7 and the scale A water manome...

Page 452: ...g list symptoms with probable causes and remedies References are made to other charts also to various sections in this man ual which list correct remedies and procedures HARD STARTING LOW STARTING R P...

Page 453: ...ctor Refer to Injector Tests under Fuel Injectors in Fuel System SECTION 6 C COOLING SYSTEM TEMPERATURE BELOW NORMAL Refer to Abnormal Engine Coolant Temperatures NO FUEL OR INSUFFICIENT FUEL Refer to...

Page 454: ...or LACK OF POWER IMPROPER ENGINE ADJUSTMENTS Check for the following 1 Governor Gap Set Incorrect Perform tune up operations as directed in Section 6 C 2 Rack Setting Incorrect Perform tune up operati...

Page 455: ...n Section 6 C 2 Improper Timing of Injectors Time fuel injectors as directed under Injector Timing in Section 6 C 3 Faulty Injectors Replace injectors 4 Lugging Engine Correct driving practices IMPROP...

Page 456: ...NIFOLD Install new restricted fitting FAULTY FUEL PUMP RELIEF VALVE NOT SEALING Make Fuel Pressure and Flow Tests and clean and inspect valve and seat assembly WORN GEARS OR PUMP HOUSNG Replace gear a...

Page 457: ...efer to Lubrication Section 0 2 Plugged Oil Cooler Clean oil cooler if oil temperature is abnormally high 3 Fuel Oil Dilution Check for fuel leaks at injector seal ring and fuel jumper line connection...

Page 458: ...ad gaskets PISTON AND LINER DAMAGED Remove and replace piston and liner PISTON RINGS WORN OR BROKEN Remove and replace piston rings PISTON PIN RETAINER LOOSE Remove BREATHER RESTRICTION OBSTRUCTION OR...

Page 459: ...llapsed or Disintegrated Replace hoses 3 Thermostat Damaged Replace thermostat 4 Water Pump Impeller Loose on Shaft Replace impeller or shaft 5 Inadequate Water Supply on Suction Side of Pump Caused b...

Page 460: ...engine Failure to do this will place excessive stress on the attached mounting when engine is raised The instructions for replacing mountings which follow cover general procedures on various types of...

Page 461: ...que on bolts 12 Secure bolts 12 with lock w ires 13 through bolt heads and holes pro vided in bracket 14 2 Position mounting assem bly at crossm em ber and install bolts and washers 10 to attach mount...

Page 462: ...Bolts 7 Plate 8 Frame Member T 3447 Figure 4 Engine Front Moufmg on Conv Cab 90 Series In Line Diesel Engine Figure 5 Engine Front Mounting on Conv Cab 90 Series 8V 71 Diesel Engine removal of upper...

Page 463: ...arts 4 If engine front mounting bracket 6 re quires replacement the pulley and damner must be removed first When installing bracket torque bolts to 85 foot pounds and torque damper hub retaining bolt...

Page 464: ...ounting Components on Alum Tilt Series with Cummins Diesel Engine identification letter is facing forward on both sup ports fig 8 Refer to Engine Mounting Bolt Torque Chart for correct bolt and nut to...

Page 465: ...TIONS SEC 7B in this manual for necessary information to disconnect transm ission rear support and to assem ble the components to provide correct load after replacing engine re ar mounting 1 Remove ca...

Page 466: ...Bracket 6 Mounting Pad on Trans 10 Frame Side Rail 7 Bracket Bolt and Washer 11 Frame Bracket Bolt Large 8 Nut and Washer 12 Frame Bracket Bolt Small T 4201 Figure 11 Trunnion Type Engine Rear Mountin...

Page 467: ......

Page 468: ...to front of heads At this point a portion of coolant flows up and out of the engine water manifold and back to radiator The remaining portion of coolant is recirculated back into water pump and engin...

Page 469: ...iven from the blower Pump draws coolant through radiator and oil cooler discharging it into lower part of cylinder block fig 3 Openings in water jackets around cylinder bores connect with correspondin...

Page 470: ...and into the upper portion of the radiator Then the coolant passes down a series of tubes where the coolant tem perature is lowered by the air stream created by the revolving fan Control of engine tem...

Page 471: ...or remove drain plug at each side of cylinder block a On models with 6 71N engines open drain cocks at bottom of therm ostat housing if equipped water pump oil cooler and cylinder block at re ar of bl...

Page 472: ...LE ENGINE IS HOT Wait until boiling ceases then add water slowly while engine is idling Install radiator cap firmly CLEANING SYSTEM Unless water in cooling system is treated with a corrosion preventiv...

Page 473: ...up preferably before and after using anti freeze solutions radiator and entire system should be cleaned with a recommended cleaning solution as follows CLEANING 1 Drain system then close cocks and ins...

Page 474: ...into the cooling system 6 C orrect condition by tightening hose clamps and fitting connections Also examine all hoses carefully and if cracked swollen or deteriorated in any way replace with new hose...

Page 475: ...uminum components IMPORTANT Alcohol or methanol base cool ants or plain water are not recommended for your truck at any time WATER TEMPERATURE INDICATOR Electric type tem perature gauge system con sis...

Page 476: ...uit Tests 1 Disconnect w ire at engine unit 2 Connect a test light consisting of a 2 candle power 12 volt bulb and a p air of test leads in c ir cuit by clipping one lead to a hot term inal and other...

Page 477: ...t must be completely submerged and w ater thoroughly agitated while heating Apply heat to the w ater and record both the tem perature at which the therm ostat begins to open and the tem p erature at w...

Page 478: ...and upper plate 4 in filger body 8 Install cover 2 using new gasket 3 Tighten cover attaching bolts evenly and firm ly Install drain plug 9 in bottom of filter body 7 Open gate valves at top and bott...

Page 479: ...elt Tension Fan belt tension on vehicles equipped with V belts should be adjusted to 120 130 pounds on new belts using J 23573 belt tension gauge Used drive belts should be adjusted to 80 90 pounds Ga...

Page 480: ...ive belts on pulleys 3 Move adjusting arm to tighten belts Adjust belt tension to 120 to 130 pounds tension 4 Tighten pivot bolt and adjusting bolt firm ly 6 71 8V 71 Diesel Engines 1 Loosen drive bel...

Page 481: ...avail able and the thickness of each is identified by notches on the shim as follows No notches 0 015 inch 1 notch 0 020 inch 2 notches 0 025 inch 6 Install flat washer and bolt While rotating pulley...

Page 482: ...led and does not require periodic lubrication FAN SHAFT AND BEARING REPLACEMENT Removal 1 Remove six fan attaching bolts and remove fan 2 Loosen fan drive belts and remove belts from fan pulley 3 On 6...

Page 483: ...ve shaft and bearing assem bly 2 3 Drive seal 3 out of pump body If seal seat 4 in im peller is not in good condition use a thin blade to pry the seal seat out of im peller Thor oughly clean the im pe...

Page 484: ...pump as shown in figure 24 is mounted on top ofthe engine oil cooler housing as shown in figure 25 The pump is belt driven by one of the camshafts An im peller is pressed onto one end of the water pum...

Page 485: ...osition of the pulley on the shaft Figure 28 Pressing Shaft Assembly into Water Pump with Special Tool J 930J so that the pulley can be installed in the same position when the pump is assembled Remove...

Page 486: ...until the im peller is flush with the large end of the body 4 Place the pulley on the bed of an arbor p ress Place a suitable rod between the ram of the press and the im peller end of the shaft then...

Page 487: ...pump outlet flange to the cylinder block Figure 33 Pressing Water Pump Shaft from Impeller 4 Remove the three bolt and seal assem blies that attach the pump to the blower assembly then use special to...

Page 488: ...f a new steel insert is to be used in the pump body make sure the counterbore in the pump body is thoroughly clean before installing a new insert D irt in the counterbore can cause m isalign ment betw...

Page 489: ...g ring over the pump out let and next to the flange 3 Using a new gasket at the bolting flange place the pump against the blower end plate cover so that the lugs on the drive coupling mesh with the lu...

Page 490: ...t the seal puller c Insert the slotted endofthearm J 22150 5 through the seal puller and position the cover stud in the slot of the arm as shown in figure 39 d With the square head screw started in th...

Page 491: ...ts inspect them care fully to make sure the nylon inserts are in place and protrude sufficiently beyond the threads to prevent leakage Under no circum stances should a standard bolt be used 10 Install...

Page 492: ...arings on the shaft CAUTION Apply pressure to the inner races of the bearings only during assembly on the shaft Figure 42 Pressing Shaft Out of Gear CAUTION A support must be placed between the pump s...

Page 493: ...conditioning larger engine water filter increased cooling etc the capacity of cooling system will vary For the purpose of obtaining an accurate cooling system capacity before adding anti freeze to an...

Page 494: ...6484631 whi ch has a special lens for this purpose b Position the viewer as shown in figure 3 and turn on viewer light A dirt clogged element prevents the light from being visible from outside c The p...

Page 495: ...every 200 miles A ir cleaners on vehicles oper ating in dust storm areas should be cleaned im mediately after such storm s occur On some vehicles having paper element an air restriction gauge indicate...

Page 496: ...ES L P inted n USA UNITED AIR CLEANER DIVISION NOVO INDUSTRIAL CORPORATION CHICA60 ILL T 5883 Figure 4 Typical Dry Element Cleaner Label 2 Remove element downward and out of clean er body Some cleaner...

Page 497: ...ning fluid until all oil and dirt de posits are removed DRY ELEMENT THOROUGH LY OF CLEANING FLUID BEFORE INSTALLING Reinstall element in cleaner body 4 Fill air cleaner cup to indicated level with S A...

Page 498: ...ent Replacement Fig 9 1 Loosen wing bolt in clamp band until bot tom pan can be lowered from cleaner body 2 At bottom of element remove wing nut Pull element downward to remove from shell 3 Install ne...

Page 499: ...ctivate indicator valve the indicator will show a red ring in the transparent area of the body SERV Figure 12 A ir Filter Restriction Indicator ICE LEVEL This is a signal that the a ir cleaner must be...

Page 500: ...celerator pull back spring Disconnect the accelerator relay rod as sembly at the carburetor Loosen the jam nut on the accelerator relay rod 2 Block pedal down firmly against floor mat 3 Hold carbureto...

Page 501: ...lve closes completely as knob is pulled out Reposition choke cable housing in clamp if there is interference before choke valve is com pletely closed Adjustment of fast idle mechanism is covered later...

Page 502: ...compressed position Rocker arm then idles on camshaft eccentric and diaphragm moves only a few thousandths of an inch to replace fuel which enters carburetor between pump strokes Thus a constant press...

Page 503: ...the valve is a weight and at other end is a spring The spring holds the valve assembly in closed position until such tim e as centrifugal force acting on valve weight begins to move the valve toward...

Page 504: ...ification number and secure the correct repair kit TROUBLE DIAGNOSIS NOTE The following information is included to serve as a guide in servicing carburetor Many tim es a carburetor has been overhauled...

Page 505: ...tep 2 Fast Idle Adjustment Set with warm engine use tachometer set to information specification 2 Throttle Return Check Proper clearance with throttle lever 1 1 5 2 Power Piston Bent or sticking disto...

Page 506: ...rburetor NOTE Fuel seepage at the bowl to a ir horn mating surface is normal This usually shows up as a discolored carburetor and is caused by wick ing of the gasket in the area Correction involves a...

Page 507: ...ion of vac uum idle stop to prevent its rotation while ad justing plunger CAUTION UNDER NO CONDITIONS SHOULD THE DIAPHRAGM EXTENSION BE ALLOWED TO ROTATE OR INTERN AL DAMAGE WILL RESULT TO VACUUM IDLE...

Page 508: ...air horn to main body then remove one long screw at forward side of air horn and one long screw next to fuel body Replace these screws with two of the short screw s to hold main body flange to throttl...

Page 509: ...consists of no additional components other than a specially calibrated carburetor and a vacuum idle stop CARBURETOR The carburetor used on C C S M equipped vehicles functions and operates the same as...

Page 510: ...p Discharge Jet No 70 70 Idle Discharge Holes Primary No 50 52 Secondary No 60 None Tertiary No 56 None Idle Tube Feed Hole No 64 68 Idle Air Bleed Cluster No 55 51 Vacuum Spark Hole 2 No 65 2 No 65 F...

Page 511: ...ined Observe fuel drained for presence of water If water is indicated regularly the fuel tank and lines should be drained and cleaned Element replacement procedure is sam e as for secondary filter whi...

Page 512: ...reely into cross shaft lever of 6 71 or 6V 53 engine or into gov ernor lever of 8V 71 engine 4 Connect rod assembly and release accel erator pedal Connect pull back spring STEEL TILT CAB MODELS Refer...

Page 513: ...engine type To adjust the linkage on all vehicles refer to figure 8 and Figure 4 Sectional View of Secondary Fuel Filter Figure 6 Accelerator Linkage for 6 71 or 8V 71 Diesel Engines Conventional Cab...

Page 514: ...rning knob until locking device is engaged To release the throttle from the locked position turn the knob one quarter turn in either direction and push the knob all the way down to return the engine s...

Page 515: ...between trunnion and spring loaded operat ing latch see fig 2 3 Operate the emergency stop without engine running to check the operation CAUTION The Emergency Stop is provided for emergency use only a...

Page 516: ...line to the fuel return passage through a restricted fit ting and back to the fuel supply tank FUEL INJECTORS DESCRIPTION The GM unit fuel injector illustrated in figure 11 is a lightweight compact un...

Page 517: ...a par ticular type of injector it is imperative that the correct injectors are used for each engine appli cation If injectors of different types are mixed erratic operation will result and may cause s...

Page 518: ...ve lifts off its seat the fuel is forced through the sm all orifices in the spray tip and is atomized in the combustion chamber When the lower land of the plunger uncovers the lower port in the bushin...

Page 519: ...r filters should not be removed while the injectors are in the engine F ilter elements should be replaced only at the tim e of complete disassembly and assembly of an injector 3 Whenever an injector h...

Page 520: ...bolts Therefore note the position of the exhaust valve bridge before during and after tightening the rocker shaft bracket bolts 4 Remove the shipping caps Then align the fuel lines and connect them t...

Page 521: ...ck does not move Figure 18 Spray Pattern Test freely it indicates that the internal p arts of the injector are damaged or dirty High P ressure Leak Test With the injector still mounted in the injector...

Page 522: ...open and injecting evenly The begin ning and ending of injection should be sharp and the fuel injected should be finely atomized CAUTION To prevent damage to the pressure gauge do not exceed 250 psi d...

Page 523: ...while 8V 71 is shown in figure 22 The governor is mounted between in such a manner that one end of the governor weight shaft injector rack into the FULL FUEL position and allow the injector to operate...

Page 524: ...r end provides a moving fulcrum on which the differential lever pivots When the centrifugal force of the revolving governor weights equal the force exerted by the high or low speed spring depending on...

Page 525: ...iring properly If any cylinder is not firing properly the injector must be removed tested and if necessary reconditioned 3 Check for bind that may exist in the gov ernor operating mechanism or in the...

Page 526: ...k age If leakage exceeds one drop per minute the seals must be replaced The fuel pump should maintain a fuel pressure at the fuel inlet passage of 50 to 70 psi at 1800 rpm engine speed Lift on the suc...

Page 527: ...ctor ily check for broken pump shaft or dirt in relief valve before removing the pump from the engine 1 Insert the end of a wire through one of the pump body drain hoies then crank the engine mo m ent...

Page 528: ...compression p ressure and the injection of the proper amount of fuel at the right time It is important that extreme care be exercised in the handling and storage of diesel fuel oil as absolute cleanli...

Page 529: ...G fig 1 Tighten jam nuts 4 Check to make sure governor lever B overrides full throttle position at governor before accelrator pedal E hits stop C Adjust if nec essary 5 If trunnion was loosened or do...

Page 530: ...free movement and be sure that the return spring moves the linkage to idle position 2 Inspect the cable housing for kinks or damaged areas If badly kinked or damaged re place the cable 3 Check to see...

Page 531: ......

Page 532: ...ressor governors on Cummins equipped vehicles is the same as covered later in this section The air com pressors covered in this manual are two cylinder piston type com pressors The rated capacity of a...

Page 533: ...n vehicle model The size shape and relative arrangement of the adjusting arm the adjusting arm bracket the Drive Coupling Figure 4 A ir Compressor Gear Drive 71 Series Diesel Engine base and the suppo...

Page 534: ...ed at regular in tervals Paper or paper fiber element type air com presso r cleaner is used on some models and should be replaced when element shows visible evidence of damage or a dirt clogged condit...

Page 535: ...om pressor crankcase 3 Lubricate com pressor cylinder walls and bearings with lubricating oil before placing com p resso r in position 4 Clean or replace any damaged or dirty air lines or water lines...

Page 536: ...removing cylinder head as follows above unloader piston then push guide down over top of piston Removal Fig 7 3 Install unloader spring and spring saddle 1 Remove air inlet elbow and discard gasket M...

Page 537: ...0 operating hours or after every 15 000 m iles clean or replace governor filters Every 3 000 operating hours or after every 100 000 m iles disassem ble the governor and clean and inspect all p arts Re...

Page 538: ...pressure 20 psi 3 When cut out pressure setting of 100 107 psi is attained lock adjuster plug with lock nut NOTE It is most important that air com press or governor cut in and cut out pressures be wi...

Page 539: ...OR FAILS TO MAINTAIN SUFFICIENT PRESSURE Dirty intake strainer Restriction in com pressor cylinder head in take or discharge cavities or in discharge line Leaking or broken discharge valves Excessive...

Page 540: ...W ater Gear Paper HI Jl 282626 B W 12 W ater Gear N one M H 282745 B W 12 W ater Gear N one M l 283031 B W 1 2 W ater Belt Paper 90 Series Dl FI 282010 B W 12 W ater Gear N one DH FH 282012 B W 1 2 W...

Page 541: ...0 NOTE The air com pressor is the only source of air for vehicles with air brakes It is most important a ir intake filters and drive belts when used be serviced at regular intervals CHEVROLET SERIES 7...

Page 542: ...ystem Trouble Analysis C h a r t 6Y 43 Generating System S p ecificatio n s 6Y 46 Integral Type Alternating Current Generating S y ste m 6Y 48 Standard 75 Amp Delco Remy Integral Type Generating Syste...

Page 543: ...on tacts the split vent The battery has three m ajor functions to p er form on the vehicle 1 It provides a source of current for starting the engine 2 It acts as a stabilizer to the voltage in the ele...

Page 544: ...ppear as a dark black spot in the center of the vent cap When the elec trolyte level drops below normal the spot will change from black to an off white color When the indicator shows water is needed a...

Page 545: ...te at which charg ing current is supplied One is the Slow Charge method the second is the Fast Charge method and the third is the Emergency Boost Charge method Before recharging the battery by any met...

Page 546: ...2 These testers have a programmed test pro cedure consisting of a series of timed discharge and charge cycles requiring approximately 2 to 3 minutes that will determine the condition of the battery wi...

Page 547: ...highest and lowest cell is less than 05 volt battery is good Good Battery Fig 3 View B If cells read both above and below 1 95 volts and the difference between the highest and lowest cell is less than...

Page 548: ...g line Charge the battery until specific gravity reaches 1 260 1 280 Before a new truck is placed in service make sure the specific gravity of the battery electrolyte is at least 1 250 preferably high...

Page 549: ...cks that project through each bushing and contact the arm ature shaft STARTING SYSTEM OPERATION The starting system consists of the battery starting motor including the drive assembly which engages th...

Page 550: ...loose corroded or dirty con nections or frayed cables If starter fails to crank engine first make sure battery is not discharged then check solenoid or magnetic switch operation If the solenoid fails...

Page 551: ...ircuit to Figure 3 Starter Automatic Disengagement and Lock Out 6V S3 6 71 8V 71 Diesel Engines fTypical sta rte r solenoid With solenoid energized starter will operate When engine is started current...

Page 552: ...relay will determine at what fre quency the relay contacts will open PINION CLEARANCE CHECK LIGHT AND INTERMEDIATE DUTY 1 The drive pinion clearance should be check ed whenever starter has been overh...

Page 553: ...rgized producing a magnetic field which pulls the plunger in Inward movement of plunger shifts sta rte r pinion into engagement with flywheel ring gear teeth and closes the main contacts in the soleno...

Page 554: ...ding Amps 13 5 15 5 13 5 15 5 13 5 15 5 Volts 5 5 5 Both W indings 65 3 73 3 65 3 73 3 Amps 65 3 73 3 Volts 10 10 10 Hold ln W inding 12 7 14 3 12 7 14 3 Amps 14 5 16 5 14 5 16 5 14 5 16 5 12 7 14 3 V...

Page 555: ...e before the engine performance is se r iously affected 1 Check condition of battery and cables as directed in BATTERY section 2 Check operation of centrifugal advance mechanism by removing distributo...

Page 556: ...opening of points at correct firing intervals and 2 Manual Advance Adjustment Retarding or advancing the point opening to compensate for various grades of fuel which may be used These timing factors r...

Page 557: ...t loosen distributor mounting clamp cap screw fig 4 and turn distributor housing clockwise to retard spark until knock is eliminated MANUAL ADVANCE ADJUSTMENT 1 After engine has been thoroughly warmed...

Page 558: ...ributor cap to housing SETTING DWELL ANGLE The point opening of new points can be checked Figure 5 Checking Breaker Arm Spring Tension V6 Engine with a feeler gauge but the use of a feeler gauge on ro...

Page 559: ...rk and increas ing fuel economy During acceleration or when engine is under heavy load the vacuum is not suf ficient to actuate the diaphragm and the breaker plate is held in the retarded position by...

Page 560: ...screw lift SPARK GENERAL INFORMATION Spark plug life is governed to a large extent by operating conditions and plug life varies ac condenser from breaker plate and wipe breaker plate clean 5 Install...

Page 561: ...es the fracture The fracture is usually just below the crimped part of the shell and may not be visible Broken lower insulators usually result from carelessness when regapping and generally are visibl...

Page 562: ...ion using a standard round feeler gauge IGNITION SYSTEM SPECIFICATIONS CAUTION Before adjusting gap file center electrode flat In adjusting the spark plug gap never bend the center electrode which ext...

Page 563: ...C DN FC FN 90 DELCO REMY 1117225 INTEGRAL 75 AM P DH DI FH FI 90 DELCO REMY 1117231 INTEGRAL OPTIONAL 61 AM P HM JM 80 1100849 1119507 61 AM P TM 80 1100849 1119515 62 AM P HM JM 80 1117754 1116374 62...

Page 564: ...the generating system used on vehicles equipped with the 1119507 two unit type regulator and the 1115827 separate field relay unit NOTE Schematic diagrams of generating sys tem s used on vehicles equ...

Page 565: ...nt regulating device is required in the regulator used with A C generator since the generator has inherent cur rent regulation as long as the voltage is controlled Cut out relay is not required with A...

Page 566: ...ped to prevent chafing the insulation 4 With engine running listen for noise and check generator for vibration If generator is noisy o r vibrates excessively it should be removed for inspection and re...

Page 567: ...balanced gen erator fan or pulley Remove generator and repair 3 A defective diode or stator resulting in an electrical unbalance To check for a defective diode or stator p er form Generator Output Tes...

Page 568: ...eter between w ire and BAT term inal on generator fig 7 3 Install a voltm eter between the generator BAT term inal and GRD term inal 4 Pull latch on regulator upward to disengage from connector then...

Page 569: ...G VOLTMETER TO POSITIVE POST ON BATTERY VIEW C CHECKING GENERATOR FIELD CIRCUIT USING OHMMETER VOLTMETER TO GROUND w ON GENERATOR WIRING HARNESS VIEW D CHECKING FOR EXCESSIVE RESISTANCE T 1 5 4 7 Figu...

Page 570: ...fied value is for an ohmmeter reading directly across the slip rings f Disconnect ohmmeter and reconnect the battery ground strap 4 If the voltmeter indicates battery voltage the regulator is shorted...

Page 571: ...noticably affected by changes in tem perature GENERATING SYSTEM WITH TWO UNIT TYPE REGULATOR NOTE On some generating system s No 2 term inal on regulator is energized by system volt age rather than by...

Page 572: ...directed previously in Step 5 9 Operate engine at approximately 2500 rpm and note voltage setting Readjust if necessary 10 Check the voltage setting while operating on the lower set of contacts as fo...

Page 573: ...d of this section 4 If voltage is not within specified range replace the regulator 5 If voltage is within specified range remove plug and turn the slotted adjuster inside regulator fig 16 Use a thin f...

Page 574: ...wire from GRD term inal and remove wiring clip On the 130 amp generator remove nuts and w ashers from harness leads at generator term in als Remove harness clip from generator then pull leads from te...

Page 575: ...lies out of cavities in brush holder 4 Position both brush assem blies in cavities in brush holder as shown in figure 18 5 Attach brush leads to term inals and secure with nuts and washers Tighten nut...

Page 576: ...necessary to remove the cavities en tirely The lower contacts are of softer m aterial use a piece of cloth with solvent to remove any discoloration IMPORTANT DO NOT USE AN ABRASIVE ON THESE POINTS Af...

Page 577: ...he 62 or 130 amp gen erator as shown in Model Application C hart pre viously The regulator is composed of transistors diodes capacitors and resisto rs which form a ACCESS PLUG TO VOLTAGE ADJUSTMENT Fi...

Page 578: ...malfunctions 1 Connect POS voltmeter lead to battery POS term inal on regulator and NEG voltmeter lead to ground on regulator 2 Adjust engine speed to approximately 1500 rpm then turn heater to mediu...

Page 579: ...ircuit is shown in figure 3 in Generat ing System General Description section previously When ignition or engine control switch is clos ed and engine is not running the field relay wind ing is energiz...

Page 580: ...from regulator 3 Remove regulator mounting screw s then remove regulator assembly INSTALLATION IMPORTANT Make sure the negative battery cable is disconnected from the battery 1 Place regulator genera...

Page 581: ...e t e l y s h o r t e d 4 D e f e c t v e dio d e B a c k b i a s D io d e s h o r t e d P o o r s w i t c h i n g w h i c h w o u l d c a u s e s h o r t e d o u t p u t t r a n s i s t o r 1 F t e...

Page 582: ...enti fication and location of following components FEED BACK CAPACITOR Cl Part A Fig 29 If both readings are zero the capacitor is de fective Visually inspect for open soldered connec tions and broken...

Page 583: ...resistor has been unsoldered from the panel board at one end merely connect an ohm Figure 32 Checking Transistors for Opens meter across the resistor an infinite reading in dicates an open Replace if...

Page 584: ...ENGINE ELECTRICAL 6Y 43 TROUBLE ANALYSIS CHART CHEVROLET SERIES 70 90 HEAVY DUTY TRUCK SHOP MANUAL...

Page 585: ...ENGINE ELECTRICAL 6Y 44 TROUBLE ANALYSIS CHART CONT CHEVROLET SERIES 70 90 HEAVY DUTY TRUCK SHOP MANUAL...

Page 586: ...y unit and note Part Number Con nect voltmeter POS lead to relay BAT terminal and NEG lead to ground If voltmeter reading is obtained voltage regulator is open or ground circuit is defective Proceed a...

Page 587: ...lowable Range at 0 Position of Adjusting Screw TEM P ER A TU R E V O LTA G E CHART NO 2 Regulator A m b ie n tTe m p D e g F 65 85 105 125 145 165 185 Voltage Setting 14 1 14 8 13 9 14 7 13 7 14 5 13...

Page 588: ...A m p Generator Bolt 20 25 With 62 Am p Generator Bolt 25 30 With 130 Am p Generator Bolt 30 35 Generator to Mounting Bracket Pivot Bolt W ith 42 Am p Generator Nut 15 20 Bolt 25 30 With 6 1 A m p Ge...

Page 589: ...nit along with the brush holder assem bly is attached to the slip ring end fram e The regulator voltage setting can be adjusted as explained later in this section The generator is air cooled by a fan...

Page 590: ...or R term inal For information relative to this relay refer to Starter Automatic Disengagement and Lock Out in STARTING SYS TEM previously PRECAUTIONS Observe the following precautions when per formin...

Page 591: ...is im pressed across diodes D5 and D6 caused by current flow through R5 R2 and R4 When the p re set voltage is reached diodes D5 and D6 con duct TR3 turns on TR1 and TR2 turn off and the generator vol...

Page 592: ...in recommended tension This can usually be done with tension gauge on the belt Tighten generator pivot bolt and adjustment arm clamp bolt firm ly TROUBLESHOOTING PROCEDURES GENERAL INFORMATION Energiz...

Page 593: ...ltage does not rise above the Operat ing Range proceed to Part b If the voltage rises above the Operating Range check the regulator lead fig 7 for tightness If satisfactory check the field coil for sh...

Page 594: ...t or if ohmmeter reading is high infinite the field coil is open c The winding is checked for short circuits by connecting a battery and ammeter in series with the field coil Note the ammeter reading...

Page 595: ...rted or grounded while being discon nected 2 Remove bolt from the electrically insulated output terminal then remove the lead Disconnect relay terminal lead from generator 3 Loosen adjusting arm clamp...

Page 596: ...bolts pivot bolts and adjustment arm clamp bolt and tighten as nec essary 3 Check all electrical connections for tight ness and corrosion Clean and tighten connections as necessary Be sure wiring insu...

Page 597: ...reases replace regulator as described later in this sec tion If voltage does not increase generator is at fault GENERATOR REPLACEMENT Due to variations in design and the equipment used the replacement...

Page 598: ...ver fig 11 2 Referring to figure 11 remove nuts wash ers and leads from F and F brush term inals Remove two brush holders and slip ring brushes with springs 3 To check for ground place one ohmmeter or...

Page 599: ...tifier cover 3 Run engine for approximately 15 minutes at 800 engine rpm to norm alize electrical system 4 Voltmeter should read 13 5 to 13 9 If nec essary to adjust turn voltage regulator adjusting s...

Page 600: ...ssion the angularity between the gearshift lever 1 and control island panel 2 after adjust ment should be 98 30 Adjustment is accomplished by rotating the adjustable clevis see Inset fig 1 at either t...

Page 601: ...ft lever through the shift pattern There must be no binding in the linkage Readjust linkage if necessary to obtain these conditions 7 Using new lock wire secure setscrew at each universal joint CONTRO...

Page 602: ...rols at control island panel become worn or damaged make repairs as described in the following text SERIES 7500 SHIFT MECHANISM Removal NOTE Key numbers in text refer to figure 4 1 At the control isla...

Page 603: ...quipped with a Fuller transm ission position range control valve on gearshift lever at least 3 inches below the gearshift knob Reconnect the air lines to the control valve and check the system for air...

Page 604: ...ow parts dry 2 Examine all parts for scoring cracks or other damage Discard all parts that are not in good Condition 3 If inspection shows oil seals 20 and 21 to be worn or deteriorated drive oil seal...

Page 605: ...joint assem bly on prop shaft type shift rod Install setscrew 15 and tight en firm ly 4 Install gearshift lever grip 28 IMPORTANT On vehicles equipped with a Fuller transm ission position range contro...

Page 606: ...e new oil seal into bore of housing NOTE Coat outer diameter of oil seal with a light coat of sealing cement prior to installation Assem bly NOTE Key numbers in text refer to figure 6 1 Position selec...

Page 607: ...ion 2 With all parts in NEUTRAL position carefully place remote control assem bly on trans m ission cover 3 Install remote control assem bly to trans m ission cover attaching parts Tighten the bolts f...

Page 608: ...ew 25 Tighten screw to 25 foot pounds torque and secure with lock wire 5 Install attaching parts that retain shifter shaft collar 10 to shifter shaft 11 6 Install attaching parts that hold shift lever...

Page 609: ...election lever shaft 20 onto shift finger shaft 15 Rotate selection lever shaft until selection cam and stud assem bly 6 properly en gages selection lever shaft Then rotate selection lever shaft 180 d...

Page 610: ...in spring and plunger pin shown in figure 9 Keep the remote control assem bly slightly tilted to the left as shown to prevent plunger from fall ing into the transm ission 2 Remove remote control assem...

Page 611: ...y and secure with new lock wire NOTE On vehicles equipped with Spicer 6000 Series transm issions insert shift finger stud 12 in 1st and reverse shift finger 11 Position in housing and install washer 1...

Page 612: ...fts at highest rpm possible CAUTION The transmission should not be operated if throttle linkage is not adjusted correctly because insufficient TV pressure could cause reduction of main pressure which...

Page 613: ...etely out of the neutral notch If lever is not properly located or operating adjust linkage as follows 1 Locate transm ission selector lever B against stop in 3 6 position 2 Check cable for dimension...

Page 614: ...ferring to Inset figure 15 loosien jam nuts and adjust length of push rod to dimen sion shown 3 With neutral safety switch push rod prop erly adjusted tighten jam nuts securely Figure 16 Retarder Cont...

Page 615: ...e checking for proper movement of retarder valve Use a scale to be sure movement of valve from OFF to ON position is inch 5 Have assistant release retarder pedal The retarder valve must return to the...

Page 616: ...be more effective however just riding with the driver can be very informative If remote controls are used a careful check of the remote and connecting linkage to transm is sion and auxiliary must be...

Page 617: ...essively in all shift positions If releasing the clutch tends to kill the engine then this gear posi tion has not seized In other words the transm is sion would be in two gears at the same tim e By a...

Page 618: ...rn bearings retainers etc g Thrust washers or faces worn excessively m issing etc HARD SHIFTING 1 Sliding gear tight on shaft splines 2 Insufficient chamfer of sliding gear teeth 3 Burred mainshaft or...

Page 619: ...ly from hammers drifts power chisels etc or be manufactured with in the unit during service from raking teeth etc These chips produce sm all indentation in balls and races Jamming of these hard partic...

Page 620: ...ng to prevent entry of dirt 13 Position a suitable dolly or jack under ve hicle and adjust to carry weight of transm ission 14 Remove attaching parts that retain trans m ission to transm ission rear m...

Page 621: ...r torque values for themainshaft flange or yoke retaining nut is given under Rear Oil Seal Replacement later in this section 12 Connect mechanical parking brake lever and controls when used Adjust bra...

Page 622: ...e installed height of the cushion assem bly lifting equipment removed which should be 11 16 inch Reduce shim pack if le ss than 11 16 inch and increase shim pack if more than 11 16 inch accordingly Su...

Page 623: ...al washer and rear mount ing bracket This final dimension is the thickness of shim s including special washer required at the rear mounting NOTE There may be a difference in gap be tween the right and...

Page 624: ...manual 11 Disconnect the mechanical parking brake linkage at right side of transm ission if used 12 Through the starter opening in the fly wheel housing use a pry bar as necessary to manually turn the...

Page 625: ...filter if used and add transm ission oil as des cribed in LUBRICATION SEC 0 in this manual WARNING TO PREVENT ACCIDENT AL STARTING OF V EH ICLE WHILE POSSIBLY IN A DRIVE RANGE BE SURE IGNITION SWITCH...

Page 626: ...ated air is supplied to the bottom port of the air valve and to the IN port of the control valve With the control button down air passes through the control valve and to the end port of the air valve...

Page 627: ...ission fails to make a range shift or shifts too slow the fault is most likely in the air system It is most important to check the en tire air system before condemning a single com ponent To check th...

Page 628: ...replacing worn parts the regulator still does not read within lim its regulated pressure can be changed by the addition or removal of shim s a Add shim s to raise air pressure b Remove shim s to lower...

Page 629: ...icle air pressure discon nect i air line at side port of splitter cylinder cover There should be a steady flow of air at all tim es If air gauge is available take pressure reading which should be 57 t...

Page 630: ...ater is removed Check filter regu larly under freezing conditions as air w ill not flow through an ice coated filter element SHIFT LEVER CONTROL VALVE Removal Refer to Fig 8 1 Disconnect the air lines...

Page 631: ...ial adapter plate which is attached to transm ission case 3 Remove alignment sleeve shown in figure 13 4 Remove actuating pin and spring from bore in adapter plate 5 Remove attaching parts retaining a...

Page 632: ...ng washer andpiston spring from the piston 6 Push the piston out through the input port of the regulator 7 Remove seal from piston bore of the body Cleaning and Inspection 1 Clean all metal parts thor...

Page 633: ...air pressure to remove piston do not stand in front of range shift cylinder during removal 5 Remove seals A and B from piston and replace with new seals NOTE Seal C is to be replaced at trans m ission...

Page 634: ...ving the top plate screw Individual parts can be obtained in a kit 1 Make sure jam nut locking control valve to the gearshift lever is secure 2 Make sure that top plate screw is torqued with 90 to 120...

Page 635: ...nstant air from regulator passes through the insert valve and to the backside of the piston and moves the shift bar forward DIRECT When the insert valve piston is activated by a signal or delivery of...

Page 636: ...iary transm ission by repositioning NUTS C and NUTS D as necessary 3 Check adjustment by moving gearshift lever through the shift pattern There must be no binding in the linkage NOTE Due to the constr...

Page 637: ...UNT SPICER 6041 CROSSMEMBER FRONT MOUNTING 45 55 FT LBS 95 105 FT LBS CROSS BEAM L pis FRAME CUSHION ASSEMBLY MOUNTING PLATE FRAME MOUNTING FRONT MOUNT BRACKET VIEW C FRONT MOUNT SPICER 7041 AUXILIARY...

Page 638: ...R MOUNT SPICER 7041 CROSS BEAM 90 210 FT LBS CROSS BEAM 95 105 FT LBS Torque BOLT TORQUE Specifications 3 REAR MOUNTING FRAME BRACKET VIEW D REAR MOUNT SPICER 7041 190 210 FT LBS CUSHION ASSEMBLY SPAC...

Page 639: ...s fram e Also it is essential that the aux iliary transm ission be checked for proper drive line angle adjustment as described under PRO PELLER SHAFTS SEC 4D in this manual 5 Reconnect power take off...

Page 640: ...LS LINKAGE ADJUSTMENTS HM JM80 WITH VACUUM BRAKES Refer to Fig 1 1 Disconnect the release fork pull back spring 2 Move the release fork to a position where the release bearing can be felt to just bare...

Page 641: ...with the release lever held rearward until the release bearing is just contacting the release fingers 5 Tighten lower lock nut against lower ad justing nut and connect clutch lever return spring Remov...

Page 642: ...Clutch Brake When the clutch facings wear fig 3 the re lease bearing moves in toward the flywheel Since yoke position is fixed the inward movement of the release bearing assem bly reduces the orig ina...

Page 643: ...spring loaded in the adjusting ring notches 5 Block the clutch pedal in cab down in a fully released position to remove spring load from adjusting ring inside the clutch 6 Use a large screwdriver to t...

Page 644: ...oosen lower front adjusting nut left hand threads and the low er rear adjusting nut right hand threads 4 The clearance between release bearing and yoke free travel should be 1 8 inch as shown in figur...

Page 645: ...required Master cylinder push rod ad justment and the slave cylinder push rod adjustment NOTE Master cylinder push rod adjustment is not required on steel tilt cab m odels except TM80 and TV70 Purpos...

Page 646: ...ring in cylinder bore fig 14 If not the push rod is too long and should be shortened as directed later IMPORTANT It is better to have push rod adjusted too short than for it to be too long If the pus...

Page 647: ...except TM80 and TV70 models which utilize a master cylin der mounted under the dash panel fig 15 To provide complete and proper release of clutch on these vehicles full travel of the clutch pedal must...

Page 648: ...Back off adjusting nut until the tool just fits be tween the nut and wedge 4 Remove the tool lock adjusting nut with lock nut and install the slave cylinder return spring HN JN90 EQUIPPED WITH SPICER...

Page 649: ...g in bottom of clutch housing 4 Referring to figure 7 remove cap screw and lock washer Use screwdriver or sim ilar wedge to pry adjusting ring lock free of the adjust ing ring CAUTION Use care when re...

Page 650: ...units having reservoir cover in stead of cap remove standard cover and install special cover J 8554 Connect pressure tank hose to filler cap or special cover opening Bleed air from hose before tighte...

Page 651: ...urely engaged 2 Disconnect pedal return spring 8 3 Separate pedal upper section 10 from lower section 11 after removing attaching bolt 9 1 Master Cylinder 9 Pedal Attaching Bolt 2 Push Rod Boot 10 Ped...

Page 652: ...models The unit consists of two cylinders with an integral reservoir The brake cylinder bore left side is larger than the clutch master cylinder right side Due to the different sized bores the pistons...

Page 653: ...refill with proper fluid 3 Pedal binding on shaft preventing full re turn of piston free up and lubricate pedal PERPENDICULAR TO VENT HOLES T 1007 Figure 26 Master Cylinder Filler Cap Baffle Steel Ti...

Page 654: ...m aster cylinder 3 Adjust stop screw as described previously under Clutch Pedal Stop Screw Adjustment 4 Fill m aster cylinder and bleed system as described previously under Bleeding Hydraulic System...

Page 655: ...is provided for by the external return spring REMOVAL 1 Remove return spring from clutch release fork or lever 2 Disconnect fluid line at slave cylinder 3 Remove bolts retaining slave cylinder at mou...

Page 656: ...h components during removal IMPORTANT To facilitate removal of the Long clutch cover assem bly install three hard wood blocks between the release levers and cover as shown in figure 3 On Lipe Rollway...

Page 657: ...to Fig 6 1 Remove release lever from clutch release yoke cross shaft 2 Disconnect flexible lubrication tube from top of release bearing support Remove two re taining springs from top of bearing suppo...

Page 658: ...so that it is directly in line with center of slave cylinder push rod Tighten lever clamp bolt firm ly 8 Fill grease cup with lubricant as Specified in LUBRICATION SEC 0 of this manual and turn down c...

Page 659: ...ent DRIVEN DISCS Inspect driven disc assembly for worn loose and grease or oil soaked facings Check for broken springs loose rivets or cracks in the driven disc hub Examine splines in hub for wear and...

Page 660: ...ne flywheel 4 Replace pressure plate or flywheel RATTLING 1 Weak retracting springs 1 Replace springs 2 R elease fork loose on ball pivot stud 2 Check stud and retaining spring and if necessary replac...

Page 661: ...y weighs approximately 150 pounds 5 Loosen the clutch to flywheel cap screw s alternately one turn at a tim e to avoid creating undue stresses in flywheel ring housing Tighten ball stud to 30 40 ft lb...

Page 662: ...main drive gear through release bearing sleeve and assem ble rear driven disc on tool NOTE When placing driven disc on aligning tool be sure the larger exposed portion of disc damper springs face the...

Page 663: ...own b Position intermediate drive plate in fly wheel locating the drive slots on the flywheel drive pins c Place rear driven disc in flywheel Be sure larger exposed portion of disc damper springs face...

Page 664: ...ditions 5 As the cap screw s are tightened the inch wooden blocks should fall free If they do not re move the blocks at this tim e and the clutch aligning tool 6 Install clutch brake fiber washer stee...

Page 665: ...for excessive wear If worn replace disc Make sure driven discs slide freely on drive gear splines 6 Replace facings or entire driven disc assem bly Cleaning not recommended 7 Replace bearing SLIPPING...

Page 666: ...from the hub on front of the crank shaft This option requires a special radiator with a portion of the core removed to allow the PTO power take off propeller shaft to drive directly through the specia...

Page 667: ...ng U joint flange to crankshaft hub Then very carefully move PTO drive assem bly through radiator open ing and remove from vehicle 3 If necessary to replace crankshaft pulley on the JM 80 refer to GAS...

Page 668: ...mouth on siphon hose NOTE When dual tanks are used but only one tank is to be removed shut off drain cock on op posite tank at balance line this will eliminate the necessity of draining the opposite...

Page 669: ...erly positioned and strap nuts are evenly tightened to correct torque Tighten hose fittings only sufficiently to prevent leakage CAUTION Overtightening fuel lines can cause leakage A fuel line fitting...

Page 670: ...er formation of the flare 3 Select the correct size upset flare punch One end of this punch is hollowed out to gauge the amount of tubing necessary to form a double lap flare 4 Slip the punch into the...

Page 671: ...sassem bly Refer to figure 7 for sectional view of teflon hose 1 Unscrew and remove the nipple 2 Slide the socket back on the hose by tapping against a flat surface 3 Remove the sleeve from the teflon...

Page 672: ...er before the bend of the hose as shown in figure 8 7 Remember the hose will change in length when pressurized Provide slack or bend in the hose to compensate for any changes which might occur as show...

Page 673: ...etic in strument which visually indicates the quantity of fuel in tank when the ignition or control switch is turned to the ON or IGNITION position The dash gauge consists of a permanent mag netic arm...

Page 674: ...0 ohm tank sending unit Series 70 through 80 tilt cab models have a 30 ohm dash unit and a 30 ohm tank sending unit It is important that dash gauge and sending units not be inter changed between model...

Page 675: ...n circuit between ground terminal on gauge and ground X Clean and tighten mounting bracket where contact is made between dash gauge and ground 10 Open circuit between sending unit terminal on dash gau...

Page 676: ...Muffler 9 Muffler Strap 10 Muffler Strap Band 11 Crossover Pipe 12 Crossover Pipe Support Clamp 13 U Bolt 14 Exhaust Pipe 15 Flexible Coupling 16 Clamp 17 Exhaust Pipe 18 Nut 19 Bolt Combination Frame...

Page 677: ...7 Exhaust Pipe 3 Muffler Clamp 10 Exhaust Pipe 18 Clamp 4 Shield Clamp Band 11 Frame Bracket 19 Flexible Coupling 5 Shield 12 Clamp 20 Clamp 6 Muffler to Air Cleaner Tube 13 Crossover Pipe 21 Exhaust...

Page 678: ...taken to prop erly position components in relation to each other Particular care should be given to the installation of the exhaust pipe and crossover pipe assem bly on V engines equipped with single...

Page 679: ...th local fire and safety regulations Before making adjustments on Fuel System Units be sure Electrical System is functioning properly WARNING CARBON MONOXIDE Keep cowl vent and heater intakes closed w...

Page 680: ...9 44 Quick Reference Troubleshooting Chart 9 45 Model Application Chart Power Steering Specifications 9 49 Torque Specifications 9 50 NOTE Illustrations are numbered consecutively within each sub sect...

Page 681: ...s used on some steering gears to prevent the worm shaft from flexing up and down J 16 15 14 13 12 11 10 9 8 TYPE 553D STEERING GEAR 25 jL_ 16 15 TYPE 554D AND 5550 STEERING GEAR 1 Lash Adjuster Lock N...

Page 682: ...ear indicates adjustment is required Refer to Steering Gear Adjustments and Steering Linkage later STEERING GEAR ADJUSTMENTS The steering gear assem bly is designed to provide adjustment to compensate...

Page 683: ...d Pitman arm so parts may be reassem bled in same relative position Refer to Steering Linkage later in this section for cor rect procedures 2 Loosen lock nut and turn lash adjuster fig 3 a few turns c...

Page 684: ...lubricant specified in LUBRICATION SEC 0 then check wheel pull PITMAN SHAFT LASH ADJUSTMENT 1 Center steering gear by turning steering wheel from extreme right to extreme left positions counting the...

Page 685: ...is clamped to the drag link cannot be repaired If the ball stud end assem bly is worn or damaged loosen the clamp bolt then remove the end assem bly 2 At socket end of drag link remove end plug ball...

Page 686: ...straight ahead posi tion adjust drag link end assem bly until stud fits into boss in steering arm without changing position of front wheels or steering gear Tighten ball stud nut firm ly 4 Use a torq...

Page 687: ...it removal of end stud bearing and seat Tie rod socket ends are self adjusting and require no attention in service other than periodic lubrication and occasional inspection to check end studs in steer...

Page 688: ...ricate tie rod end parts with lubricant specified in LUBRICATION SEC 0 of this manual before assembling 2 Position stud bearing 9 in end socket 3 Install stud 6 place grease seal 14 on spring seat 18...

Page 689: ...arts in that they could affect the per formance of vital components and system s and or could result in major repair expense They must be replaced with parts of the same part numbers or with equiv ale...

Page 690: ...reaker knob in ward Check operation of horn FOUR POSITION TILT STEERING COLUMN EXCEPT ALUM TILT CAB The steering wheel used on conventional cab models may be adjusted to any one of four posi tions To...

Page 691: ...actuating lever up ward toward the instrument panel to lock the column in position STEERING COLUMN AND SHAFT CONVENTIONAL CAB MODELS REMOVAL Fig 15 1 Disconnect directional signal and hazard warning l...

Page 692: ...yoke off steering gear worm shaft then twist and turn the shaft assem bly as required to remove from vehicle DISASSEMBLY Fig 18 1 Remove screw attaching directional signal control lever to control ass...

Page 693: ...bind Replace parts which do not operate smoothly 4 Clean all the parts and inspect for damage or wear and replace all the parts which are not in good condition ASSEMBLY 1 If previously removed press l...

Page 694: ...d instru ment panel supports to 15 to 20 foot pounds torque 8 Install steering wheel as described under Steering Wheel Replacement previously NOTE If steering wheel clunking is audible refer to Steeri...

Page 695: ...ork washers 10 fall off the center cross 14 Discard cork washers 5 Remove lubrication fitting 13 from center cross 14 6 Remove two tube yoke snap rings 2 then tap yoke tube 6 with a plastic hammer unt...

Page 696: ...Trim Panel 15 Lock Plate 16 Spring 17 Detent Sleeve 18 Bolt 19 Lock Washer 20 Cap 21 Bushing Liner 22 Bushing 23 Seal Retainer 24 Seal 25 Bushing Bracket 26 Intermediate Shaft 27 Lower Shaft 28 Nut 29...

Page 697: ...and two snap rings 6 Install bearing sleeve in column upper bearing INSTALLATION Fig 21 1 Position steering column upper and inter mediate steering shaft steering column seal and seal plate in vehicl...

Page 698: ...ENT ALUM TILT FIG 23 REMOVAL 1 Remove steering wheel as described pre viously under Steering Wheel Replacement 2 Scribe an alignment mark on lower steer ing shaft clamp yoke and steering gear worm sha...

Page 699: ...ace support bracket in position against cab steering column support 5 Position cap over rubber liner being care ful to contain the ends of the liner within the re tainer ribs of the cap 6 Install the...

Page 700: ...lock w ashers and flat w ashers Tighten bolts to 25 to 30 foot pounds torque 6 Position steering column trim panel in place and install four attaching screw s and washers 7 Install steering shaft upp...

Page 701: ...shaft IMPORTANT Check to make sure match marks on lower or intermediate shaft clamp yoke or coupling and steering gear worm shaft are aligned 3 Install bolts nuts and washers which at tach steering ge...

Page 702: ...sary to slightly spread the Pitman arm to facilitate in stallation 3 Install bolt washer and nut and tighten nut to 90 110 foot pounds torque 4 Connect connecting link ball stud to Pitman arm install...

Page 703: ...Bolt 15 20 Except F 070 Front A x le Nut 400 Steering Upper Shaft Lower Bearing With F 070 Front A x le N ut 180 240 Stop B o lt Nut 8 12 Steering Gear to Fram e Bolt Steering Shaft Coupling to Worm...

Page 704: ...could result in major repair expense They must be replaced with parts of the same part numbers or with equivalent parts if replacement becomes necessary Do not use replacement parts of lesser quality...

Page 705: ...ich supplies hydraulic fluid to either side of the power cylinder piston as required depending on the position of the valve The pressure used to operate this system is supplied by either a vane type o...

Page 706: ...o proper specifications Refer to FRONT END ALIGN MENT SEC 3A of this manual for proper pro cedures for checking front end alignment Im proper tire inflation will also affect operation of the power ste...

Page 707: ...p to steering gear pressure line at pump Connect a 0 to 2000 psi pressure gauge J 22181 to the pump outlet then connect a shut off valve between the pressure gauge and pressure line fig 4 Make sure al...

Page 708: ...is used be tween the control valve and right and left power cylinders Tag each tube or hose prior to removal to insure installation in same relative location All tubes hoses and fittings should be in...

Page 709: ...from 1000 to 1100 psi depending upon the road surface vehicle weight and pressure relief setting in the pump During normal straight ahead driving the steering wheel effort w ill be approx imately the...

Page 710: ...tion 5 Move dust cap down on yoke tube and bend tangs down to secure in position 6 If not previously installed position Pitman arm on Pitman shaft NOTE Pitman arm and shaft have matching blank serrati...

Page 711: ...ce Chart later 1 Hard steering while driving 2 Poor return of steering 3 Leads to one side or the other 4 Momentary increased effort on fast turn 5 E xcessive wheel kickback 6 Steering wheel jerks 7 H...

Page 712: ...l plunger 11 starts to move back thereby providing flow control through passages 4 6 and 7 with 7 being the suction or intake part of the pump Supercharging occurs as a result of pressure oil in passa...

Page 713: ...ED LEGEND DISCHARGE OIL 12 SUPERCHARGE OIL HIGH PRESSURE OIL RESERVOIR AND RETURN OIL RING ROTOR LEAKAGE OIL VIEW B PUMP OPERATION HIGH SPEED T 1166 Figure fi Power Steering Hydraulic Pump Operation C...

Page 714: ...driven hub drive hub or adap ter were removed install as follows a Place key in pump drive shaft slot then press pump driven hub onto pump shaft and secure with nut and washer Tighten nut firm ly b P...

Page 715: ...ut can be passed through the orifice to the power cylinder This con dition usually occurs only at low drive speeds The large spring chamber is connected to the pressure port through an orifice Pressur...

Page 716: ...sconnect hose at pump and secure ends in raised position to prevent drainage of oil from pump 2 Install caps at pump fittings to prevent drainage of oil from pump 3 Remove drive pulley attaching nut 4...

Page 717: ...rvoir when pressure exceeds specified maximum of 1000 to 1100 psi NOTE At regular intervals the fluid level in the reservoir should be checked and fluid added when level is more than two inches below...

Page 718: ...bubbles or oil will appear milky Small amounts of air cause extremely noisy oper ation If air is present in oil accomplish the fol lowing a Tighten all fittings and bolts b Check the entire system for...

Page 719: ...ng Test 2 and comparing it with Test 1 Test 2 is Performed With the Oil Circuit Closed Set engine idle at 450 rpm and turn the shut off valve of gauge to the closed position NOTE Shut off valve must b...

Page 720: ...tilt cab models the power cylinder is bracketed to the front axle at one end and to the steering tie rod at the other end Stationary metal tubes and flexible hose as sem blies carry hydraulic fluid to...

Page 721: ...d do not bind when wheels are turned 5 Bleed the hydraulic system and bring fluid to proper level as previously directed under Bleed ing The Hydraulic System POWER CYLINDER SEAL REPLACEMENT REMOVAL Re...

Page 722: ...ADJUSTMENT AXLE MOUNTED CYLINDER Adjustment dimensions for all axle mounted cylinders are shown in figure 16 Before fully tightening clamp to tie rod push steering knuckle against stop in full left tu...

Page 723: ...rod on steering arm s rotating socket ends as necessary to align parts The upper and lower cupped washers must be parallel when no power or pressure is applied to the tie rod Install stud nuts and ne...

Page 724: ...ull Fill to proper level of reservoir A ir in the oil Locate source of air leak and correct 3 Leaks at the 0 R in g seal cut Replace 0 Ring seal reservoir 0 R ing improperly installed Install seal pro...

Page 725: ...al oil leaks wipe gear thorough ly and make sure source of leakage is determined Loose hose connections Damaged hose Adjuster plug seals Torsion bar seal Tighten Replace Replace seal Replace torsion b...

Page 726: ...leakage Add lubricant where needed as described in lubrication Sec 0 of this manual Inflate to recommended pressure If all of the above checks do not reveal the cause of hard steering make the followi...

Page 727: ...remove restricting object or replace hose a Leakage at valve rings valve body to worm seal b Loose fit of spool in valve body or leaky valve body Remove gear from truck for disassembly and replace sea...

Page 728: ...Maxim um P S I 1100 1200 M inim ym Capacity Per Minute 2 35 G P M of Autom atic Transm is sion Fluid at 170 F When Operating VANE TYP E PUMP V IC K ER S Pum p at Idle Speed Against 665 735 P S I M a...

Page 729: ...ster Plug Except 568 DV 64 Nut 50 110 R H Drag Link to Idler Arm S tu d With F 160 Front A x le Nut 125 150 Type 568 DV 64 Nut 50 75 Power Steering Junction Block to Frame Bolt Control Valve to Steeri...

Page 730: ...ite valve stem on inner tire and rim assem bly 2 Install rim clamps and nuts Position and finger tighten 3 Starting at bottom tighten No 1 nut to 15 to 20 foot pounds torque 4 Torque nuts 2 3 4 5 and...

Page 731: ...TYPE WHEEL 5 3 o 4 1 1 6 STUD CAST TYPE WHEEL number or with an equivalent part if replacement becom es necessary Do not use a replacement part of le sse r quality or substitute design Torque values m...

Page 732: ...3 m is alignment Tires should be checked periodically to prevent excessive damage caused by these conditions INFLATION OF TIRES Underinflation is the greatest cause for loss of tire life expectancy T...

Page 733: ...e differential dual tires should have the same overall diameter within inch On tandem drive rear axles without an interaxle differential tires should be matched within closer lim its to assure maximum...

Page 734: ...ollowed SYNTHETIC TUBES When installing synthetic tubes coat both sides of the flap if used inner diameter of tube and inside of tire beads with a solution of neutral vege table oil soap Use a brush o...

Page 735: ...530 3730 3920 4120 4300 9 00 20 E 3560 3770 4000 4210 4410 4610 9 00 20 F 3560 3770 4000 4210 4410 4610 4790 4970 5150 10 00 15 F 3580 3780 3980 4170 4370 4540 10 00 15 G 3580 3780 3980 4170 4370 4540...

Page 736: ...80 4450 10 00 20 F 3760 3970 4180 4380 4580 4760 10 00 20 3760 3970 4180 4380 4580 4760 4950 5120 5300 10 00 22 F 4000 4230 4450 4660 4870 5070 10 00 22 4000 4230 4450 4660 4870 5070 5260 5450 5640 10...

Page 737: ...AND TIRES 10 8 IMPORTANT At regular intervals wheel nuts should be checked for tightness A noticeable noise or vibration could indicate loose wheel nuts CHEVROLET SERIES 70 90 HEAVY DUTY TRUCK SHOP M...

Page 738: ...unit replacement Notches in grille are provided for this purpose 1 Remove eight cro ss recess screw s which attach grille to radiator shell Remove grille 2 Place grille in position at radiator shell...

Page 739: ...olts depends on model which attach each side of shell to radiator support mounting brackets figs 5 and 6 or remove bolts each side at mounting pad NOTE On some models mounting bracket fig 5 is inverte...

Page 740: ...rt bracket is removed 2 Remove all bolts nuts and washers secur ing mounting bracket to frame rail to radiator shell and to radiator core support if involved 3 Remove mounting bracket fig 5 or 6 In so...

Page 741: ...ight and left and center panels REMOVAL Refer to Fig 9 1 Raise both hood side panels and support with attached props 2 At front of hood center panel remove two attaching screw s washers and nuts 3 Und...

Page 742: ...end near frame rail 2 Remove the bolt nut and lock washer from hood right and left side hinge pins 3 Support weight of hood at each hinge pin then pull the pin from hinge Lower hood tc allow hinge st...

Page 743: ...or removing shim s located between the hood forward panel and the hinge strap fig 13 Note the proper position of shim s when installed The height of hood front end is also adjustable by means of slot...

Page 744: ...ts attaching braces to hood 4 Inspect hood fiberglass in area of skirt mounting and repair if necessary To install fender skirts reverse above procedure Figure 16 Fiberglass Hood Fender REPAIR OF FIBE...

Page 745: ...erglass repair m aterials avoid contact with skin and never work near fire or flame If m aterials should come in contact with skin wash thoroughly with soap and water as soon as possible CHEVROLET SER...

Page 746: ...A Switch Differential L o c k 4A Switch Electric C h o k e 6M Switch Engine Brake 6C Switch Engine Brake C lu t c h 6 C Switch Engine O v e r h e a t 6K Switch Fuel P ressure 6C Switch Heater C o n t...

Page 747: ...or Terminals MAINTENANCE AND REPAIR All electrical connections must be kept clean and tight Loose or corroded connections may cause a discharged battery difficult starting dim lights and possible dama...

Page 748: ...which follows The tabulation lists each terminal letter the circuit it carries and the size color and pattern of the wire which con nects to each terminal Connector Replacement NOTE Wiring connector t...

Page 749: ...ro m S tart Switch 16 M aroon A uxiliary S ta rt Switch and S ta rte r M agnetic Switch 16 Blk BZ JACOBS ENGINE BRAKE C lutch Sw itch M icro B uffer S w i t c h 16 Blk CS AIR CONDITIONING A C Switch O...

Page 750: ...Blk Blk G rn Blk CHASSIS JUNCTIONS Terminal posts on junction blocks are num bered to correspond with numbers shown in sym bols on applicable wiring diagrams CONVENTIONAL CAB MODELS The chassis junct...

Page 751: ...le when circuit breaker is open The circuits are de energized when an overload condition exists or when the button is pulled out A 30 amp automatic reset type circuit breaker fed from the battery bus...

Page 752: ...Check 4 Also 5 Instrum ent Lamp Bulbs Speedom eter Oil T em perature Gauge A ir R estricto r Gauge B rake A ir Gauge A m m eter T achom eter V oltm eter Oil P re s s u re Gauge A ir Gauge Fuel Gauge...

Page 753: ...nk is connected into the major wiring harness feed circuits fig 11 The fusible link is incorporated as part of the wiring system to provide increased overload protection to electrical circuits except...

Page 754: ...ter becom es inoperative disconnect cable at rear of Figure 11 Fusible Link speedometer head and adapter and check to make sure cable and drive gear on transm ission are operating properly This can be...

Page 755: ...eriously affect speed ometer operation ELECTRIC SPEEDOMETER A permanent magnet AC generator sending unit is mounted on the speedometer adapter at rear of transm ission fig 1 2 and is driven by the tra...

Page 756: ...ect the problem replace the horn assem bly AIR HORN Air horns used as standard or optional equip ment on som e models are mounted on pedestals attached to the cab roof panel Air pressure to horns is c...

Page 757: ...t an estimated 10 m p h If a steady voltage indication of approximately 1 1 2 volts is indicated replace defective speedometer If no voltage is indicated proceed to next step Disconnect wire at S term...

Page 758: ...minals on connector Test V3 If zero repair open battery circuit if between 10 and 16 volts proceed with next step Connect ohmmeter between 0 and connector at rear of speedometer Operate vehicle a mini...

Page 759: ...ions at relay The marker lamp switch on instrument panel is connected in series with main light switch and operating coil of I C C marker lamp relay oper ating coil at terminal No 3 When the main ligh...

Page 760: ...n con trol switch in opening Engage lock tangs of wir ing connector to switch Make sure lock tangs are fully engaged by attempting to separate Insert switch into panel opening then install switch re t...

Page 761: ...ure equipped with the tandem rear axle When switch lever is positioned in LOCK position the DIFF LOCK tell tale lamp illum inates Refer to REAR AXLE AND CONTROLS SEC 4A of this manual for information...

Page 762: ...ists the buzzer will sound but only the tell tale light connected to that circuit will illuminate If alarm buzzer or rectifier assem bly does not operate properly replace the complete unit COOLANT LOS...

Page 763: ...d tell tale lamp bulbs from each gauge and unit 4 Each gauge or unit is retained in the cluster by two mounting brackets Remove wiring from connector or terminals at rear of gauge or unit then remove...

Page 764: ...sconnect drive cables lines wiring con nected to term inals and illumination and tell tale lamp bulbs from each gauge and unit 4 Each gauge or unit is retained in the clus ter by two mounting brackets...

Page 765: ...ne tell tale and a low air tell tale The gauge panel located in console to right of driver as shown in figure 19 contains a cluster of five to nine gauges Standard gauges include the engine temperatur...

Page 766: ...to the sending unit located in the engine Refer to RADIATOR AND SURGE TANK SEC 13 of this manual for information applicable to the sending unit located in the radiator HI BEAM TELL TALE GRN WHT CR TR...

Page 767: ...system voltage to rise to normal level If the hand goes over to the right hand segm ent an over charge condition exists If either a continuous undercharged or over charged condition exists check the c...

Page 768: ...Sender unit in tank in corporates a 90 ohm resistor strip AMMETER GAUGE The ammeter gauge is identified by AMP ERES on the instrument panel and indicates rate of charge or discharge battery is receiv...

Page 769: ...el Alum Tilt Cab Models Typical dicates the condition of the paper air cleaner ele ment More than 25 inches of water indicates a clogged air cleaner elem ent To service air cleaner element refer to LU...

Page 770: ...By referring to applicable wiring diagrams circuits may be tested for continuous circuit or shorts with a low reading voltmeter or a conven tional test lamp HEADLIGHTS All vehicles covered by this ma...

Page 771: ...t 25 feet fig 22 To obtain correct adjustment beam adjustment should be made with the vehicle loaded with the normal average load it w ill be carrying during the majority of its operation Tires should...

Page 772: ...ug over blade type term inals on back of sealed beam unit 2 Install headlamp assem bly in panel opening and rotate to engage mounting ring tabs with ad justing screw s 3 Using a hooked tool pull out o...

Page 773: ...32 candlepower BULB REPLACEMENT Removal Remove lens retaining screw s then remove lens and gasket from housing P ress bulb inward and turn counterclockwise to remove Installation Refer to Specificati...

Page 774: ...e dome light mounted above the console and the sleeper com partment light are controlled by a separate ON OFF type switch at the base of each light BULB REPLACEMENT Series 70 80 Tilt Cab Models Fig 25...

Page 775: ...off the lights pull the plunger out If directional tell tale on instrument panel flashes in one position but not the other check for the following 1 Directional lamp bulb burned out 2 Directional tel...

Page 776: ...activate the system To cancel or turn off the lights move turn signal lever up or down The hazard warning signal lever is spring loaded and will cancel the hazard warning lights when released by movem...

Page 777: ...to gain access to switch Remove two screw s which attach switch to floor panel and pull wiring connector plug off switch term inals Push wiring connector plug onto switch term inals Position switch on...

Page 778: ...r ing harness connector 4 Remove screw attaching control lever to switch and remove lever 5 Remove two screw s which attach hazard warning switch to housing 6 Remove three screw s which attach control...

Page 779: ...turn signal switch lever SWITCH REPLACEMENT 1 Disconnect wiring harness connector from chassis wiring harness connector located below steering column 2 Remove control assem bly wiring from the Figure...

Page 780: ...t cab models remove the steering wheel as ex plained in MECHANICAL STEERING SEC 9A of this manual and check for a worn or damaged cancelling cam LIGHT BULB DATA BULB NO CANDLE POWER H E A D L A M P Du...

Page 781: ...nt Opening I n A C C ES S O R Y FE E D R E L A Y Opening Voltage Range 3 7 5 2 Alum Tilt Cab M ake Delco Rem y G E N E R A T O R T E L L T A L E R E L A Y M o de l 1115841 M ake Delco Rem y A ir Gap a...

Page 782: ...S 7 0 9 0 H E A V Y D U T Y T R U C K S H O P M A N U A L GROUND DASH ENG i f 9 GRD STRAP J DASH t 2 Z o 2 o 30 2 Figure 37 Cab Engine and Chassis Wiring HI Jl MH Mi 90 Sheet 1 of 7 CHASSIS ELECTRICA...

Page 783: ...E S 70 9 0 H E A V Y D U T Y T R U C K S H O P A A A N U A L GENERATOR CONTROL SWITCH TEMPERATURE GAUGE Figure 37 Cab Engine a n d C h a ssis W irin g HI JI M H M I 9 0 Sheet 2 o f 7 CHASSIS ELECTRICA...

Page 784: ...C H E V R O L E T S E R IE S 7 0 9 0 H E A V Y D U T Y T R U C K S H O P M A N U A L Figure 37 Cab Engine and Chassis Wiring Hi Jl MH MI 90 Sheet 3 of 7 CHASSIS ELECTRICAL A N D INSTRUMENTS 12 38...

Page 785: ...z L J i i J TRL ICC MKR LP RELAY t r u c k REAR I C C MKR LPS y i4 LT GRN r 6 T A N J l _ 14 LT GRN 16 TAN f4 LT GRN 6 TAN HEADLAMPS CHEV MODELS UPPER a LOWER BEAM UNIT UPPER BEAM UNT m m UPPER BEAM U...

Page 786: ...1 W H T I 4 0 R N Z O R flf o O I4 W H T A 4 0 R N 6 F 0 EM RG PARK AIR STOP SW BRKE STOP LT SW y 8L T c 18 LT CRN R H HEATED MIRROR 8 B iff 6 18BLK c L H HEATED MIRROR R PO I K4 7 5 COMMON 16 BRN WHT...

Page 787: ...V t ax le s h f t sw r 2 BLK RB6ED j SPCEOO ADAPTER T vf I A X L ES H F TM T R B BLK SMOOTH j eau u SOL AIR VALVE TANDEM AXLE 14 BLUE WHT CR TR HEATER SLOWER CONTROL SW BLOWER CONTROL SW J6B R N e YEL...

Page 788: ...STR PANEL HARN ENG HARN TO HD LB 8 PARKING LR HARN STOP 8 TAIL LR FRT EXT HARN TO REAR STOP 8 TAIL LR HARN REAR STOP 8 TAIL LP HARN TO STOP 8 TAIL LR ASM RELATED CIRCUITS WSTR PANEL HARN STOP 8 TAIL L...

Page 789: ...A A A N U A L 4 6 V BAT F R A M E M T D DU6L I2V BAT FRAME MTD R RO T 6 8 STARTER STARTER NTERLOCK HORN VOLTMETER AMMETER RPO U3I WRE WITH RED SLEEVE GENERATOR Figure 38 Cob Engin e a n d C h assis W...

Page 790: ...S E R IE S 7 0 9 0 H E A V Y D U T Y T R U C K S H O P M A N U A L CONTROL SWITCH TEMPERATURE g a u g e FUEL GAUGE Figure 38 Cab Engineand Chassis Wiring HN JN 90 Sheet 2 of 5 CHASSIS ELECTRICAL AN D...

Page 791: ...0 G R A Y f v AMMETER R Pa I f8 GRAY O I L GAUGE 1 8 GtNTY VOLTMETER 8 GRAY j TACHOMETER GRAY I S GRAY AJR GAUGE LO AIR T T LOW AIR SW f o J V 4 a f GRN TR 18 GRAY 8G R A Y 4 18 GRAY 4 INSTRUMENT LCT...

Page 792: ...R L P L U G 6 RPO U 6 3 N O T E T E L PLUGS SHOm LO O KN G T O PEN M ATNG END R H S T O P T A IL 8 DlR LP l k s t o p t j u l a W R L P AIR STOP SW EMERG PARK 0RKE STOP LT SW BACK UP LPS 2 SPEED AXLE...

Page 793: ...FLE X GAUGE TO N S TR R W C L I I M X R M STR PANEL AT STEERIN G COLUftM UNDER N S TR PAN EL AT FU EL GA ENG HARN TO H O LR 8 PARKING LR HARN STOP 8 TAIL LR FRT EXT HARN TO REAR STOP 8 TAIL LP H AR N...

Page 794: ...IN G L E L IN E CONN DH FH 9502 ONLY o T E R M IN A L O R CONN T ER M IN A T IO N S P L IC E L IN E F U S E B U S B A R R ELA T E D CIRCU ITS C IR C U IT B R E A K E R BAT AUX F E E D FOR M U LTIPLE C...

Page 795: ...0 1 FR A M E I 4 ic AAW BAT BOX HTR 5 ip 5 J P 6V 0 0 6V 6V 00 6V BATTERIES 4 rfl STARTER AM M ETER GENERATOR STARTER INTERLOCK MASTER CIRCUIT BREAKER HORN RADIO GAUGES O IL P R E S S S E N D E R M 7...

Page 796: ...W BACKUP LR A IR COND HEATER JACO BS ENGINE BRAKE Cfc 1 6 2 BZj 16 NOTE SW CONTACT SHOWN IN C L O S E D PO SITIO N W ITH CLUTCH P E D A L IN NORM AL PO SITIO N l_ _ r MICRO B U F F E R SW R E A R B LO...

Page 797: ...RH CT TAN CAB FRT M KR L PS 1 6 B R N 1 6 B L U E S P A R E I C C MKR LPS B L K B R N 4 RED C R N 14 Y E L L D YELL 16 RED ISBLK f C C MKR L P S _ i 5 I2 R E D S T O P L P S 1 2 G R N R H DIR LPS 1 2...

Page 798: ...LP R EA R WRG HARN ASM FC FN9502 ONLY J L H A M t H AIL V 3 T 7 A WAY C O NN fSTOP TAIL B U LP FRT WRG HARN ASM T01 fnr nr 1 rt it i u r n n n c J C 0 N N s t o p t a il B U LP REAR WRG HARN ASM J U 5...

Page 799: ...m m e t e r GENERATOR MASTER CIRCUIT BREAKER HORN RADIO 2 W H T 12 B L K W W I BAT B O X H TR I 1 UPPER O A W v j I I 4 I BAT BOX HTR I M L O W E R 1 4 O w v w j REV C II CIR BRKE MTG BRKT FRAME CAB...

Page 800: ...fY M f __ Ctr 8 j I bW ht m f 7 18 G R N 3 16 G R N Gx 16 l o c o o l a n t HOT ENG SW DIFF LOCK T T SOL AIR VALVE 4 az 6 f f y a j i LO OIL SW B T 6 v4 B O R G 1 t WHT RED T R BACKUP LP 44 HTR BLOWE...

Page 801: ...6 IB BLUE 4 R E D G R N 14 Y E L L 2 YELL cn I C C MKR LPS BODY BUILDERS REF 6 yBLU E SPARE 1 12BLK ICC MKR LPS zr i t I2 RN Tail LPS x o 5 SEM I T R L P L U G R H FRT DIR PK LP R H DIR T T I2 B R N T...

Page 802: ...Y D U T Y T R U C K S H O P M A N U A L GHO CAB ALL MODELS DASH 4 4 GFtO S T R O P ENGINE GRO ENGNE FRAME MTD BAT tram s t 2 B lk fram e RPO Figure 41 Cab Engine and Chassis Wiring HM JM 80 Sheet 1 of...

Page 803: ...R U C K S H O P M A N U A L IGNITION CONTROL SWITCH BRAKE WARNING T T R PO JL4 VAC MODELS LOW VAC ALARM BUZZER R PO JL4 VAC MODELS TEMPERATURE GAUGE Figure 47 Cob Engine and Chassis Wiring HM JM 80 S...

Page 804: ...K T T 3 W HT 2 RED TR IBGRN WHT CR TR DIFF LOCK T T 18 W HT 2 RED TR INSTR LR TAKEOFF CONNECTOR 18 GRAY S j VAC GA R PO JL4 e GRAY VAC GA WHEN USED 18 GRAY zJ 18 GRAY 4 IB GRAY t8 GRAY 18 GRAY t8 GRAY...

Page 805: ...R Lf r SEI T L PLUG 7 tftRL RPO U87 BRN TAIL L P S r 8LK LC C MKR LTS 4 W H T 9EM T R L PLUG 6 W E R P O U05 WOTEr T R L PLUGS SHOMN LOOKING AT OPEN MATNG END s 013 0 3 1 8 OK BLUE CZ2 R H FRT OR LP 5...

Page 806: ...IE S 7 0 9 0 H E A V Y D U T Y T R U C K S H O P M A N U A L 2 SPO W S WPER a SHER BACK UP LPS 2 SPEED AXLE 1MCN HEATER Figure 41 Cab Engine and Chassis Wiring HM JM 80 Sheet 5 of 6 CHASSIS ELECTRICAL...

Page 807: ...UNDER M S TR P M C L AT STEERING COLUMN U K E R N STR PANEL AT FUEL GA ENG HARN TO HD LP a PARKING LR HARN A T HEAOLAMP A m STOP a TAIL LR FRT EXT HARN TO REAR STOP a TAIL LP HARN REAR s to p a ta il...

Page 808: ...UAL I2V BAT FRAME MTD RPO T68 HJ JJ70 ONLY SINGLE I2V BAT FRAME MTD STARTER STARTER INTERLOCK STARTER INTERLOCK HV JV70 ONLY HORN v o l t m e t e r AMMETER WIRE WITH RED SLEEVE s GENERATOR TRANS l 0 0...

Page 809: ...S E R IE S 70 9 0 H E A V Y D U T Y T R U C K S H O P A A A N U A L CONTROL SWITCH t e m p er a t u r e ga u g e Figure 42 Cab Engine and Chassis Wiring HV JV 70 Sheet 2 of 6 CHASSIS ELECTRICAL A N D...

Page 810: ...WHT 2 RED TR WHT 2 RED TR 18 WHT 2 RED TR iP WHT 2 RED TR INSTR Lfi TAKEdFF CONNECTOR 2 0 G R A Y y AMMETER R PO 6 GRAY OIL GAUGE 18 GRAY VO LTM ETER 8 GRAY 4 X TACHO M ETER 18 GRAY H r 11 F U E L G A...

Page 811: ...R L P yO r SEM I T R L P L U C 7 W IRE R P O UB7 _ BLK IC C MKR LT C G R A Y T R A IL E R C A B L E S Y E LL L H D IR LP 1 _ v RED STOP L P S 4 GRN RH D H L P O y p j BRN TAIL LPS M BLK LC C MKR LTS 4...

Page 812: ...L STOP SWITCH EMERGENCY PARK BRAKE STOPLIGHT SWITCH R PO J7 4 TRA ILER EMERGENCY STOPLIGHT SWITCH R PO J9 I 2 SPD W S WIPER a WASHER BACK UP LPS 2 SPEEO AXLE WHEN U SE D HEATER Figure 42 Cab Engine a...

Page 813: ...K S ELEC T O R SW W flE TO F U EL GAUGE TO N S T R R W C L I ENG HARN TO HD LR 8 PARKING L fi HARN UNDER M S TR M N E L AT STEER IN G COLUMN U W G R 6 m A V C L AT FU EL GA STO P TAIL LR FRT EXT HARN...

Page 814: ...C H E V R O L E T S E R IE S 70 9 0 H E A V Y D U T Y T R U C K S H O P M A N U A L f Figure 43 Cab Engine and Chassis Wiring TM80 Sheet 1 of 6 CHASSIS ELECTRICAL A N D INSTRUMENTS 12 68...

Page 815: ...F LOCKED OPEN ACCESSORY BAT i ACC CONNECTED 1 8 OK BLUE ENGINE OVERSPEED T T DIFE LOCK T T OIL PRESS GA WATER TEMR GA LOW AIR T T LOW OIL T T 18 PINK DISTRIBUTOR 16 5 4 3 2 V 6 CYL ENG SHOWN FIRING OR...

Page 816: ...PEED A X LE WHEN USED DUAL SPD W S WIPER WASHER Q 14 PINK CH 14 PlNK Qf 14 DK GRN AXLE SHIFT SWITCH Z I4G RN U 14 BLK I6 B L K x r 6 S L K o e e S P E D 0 ADAPTER H 4 BLK f3j 14 B L K T 14BLK A X L E...

Page 817: ...L E T S E R IE S 7 0 9 0 H E A V Y D U T Y T R U C K S H O P A A A N U A L HEATER r a d io r p o U63 Figure 43 C ab Engine a n d C h assis W irin g T M 8 0 Sh eet 4 o f 6 CHASSIS ELECTRICAL AND INSTRU...

Page 818: ...PS 12BLK I C C MKR L T S y IOWHT 1 TRAILER CABLES L H PARK LP CHEV ONLY SEMI TRL PLUG 6W IRE R PO U 65 14 Y E LL L H D IR LP i 14 RED STOP L P S I4GRN R H D IR LP 1 4 BRN TAIL LPS V 9 N Q T E T R L PL...

Page 819: ...M IN ATIO N S P L IC E TR L WRG HARN TO TR L CABLE ASM UNDER CAB AT C A8 REAR D IR EC T SW ASM TO INSTR PNL H A R N IN S T R PANEL HARN TO HDLP PARK LR HARN E N G HARN TO STO P TAIL LP FRT E X T H A R...

Page 820: ...S 70 9 0 H E A V Y D U T Y T R U C K S H O P M A N U A L CAB GROUND ENGINE GROUND C A B lH EN G IN E i H i FRAME J l f RAME Figure 44 Cab Engine and Chassis Wiring TV70 Sheet I of 6 CHASSIS ELECTRICA...

Page 821: ...E A V Y D U T Y T R U C K S H O P M A N U A L CONTROL SW ITCH OIL PRESS GAUGE WATER TEM P GA FU EL GAUGE LOW AIR ALARM BUZZER Figure 4 4 C ab Engine a n d C h assis W irin g T V 7 0 Sheet 2 o f 6 CHAS...

Page 822: ...B LK Y E L L STR LOW OIL T T LOW OIL SW le B L K 18 BLK YELL 5 TR 0 DK GRN WHT STR HOT NG SW 1 S B LK Q 18 DK GP N W f STR DK Q RN 1 14 B L K AXLE SHIFT SWITCH 16 B L K SPEEDO ADAPTER 2 B L K 4B LK 14...

Page 823: ...O L E T S E R IE S 7 0 9 0 H E A V Y D U T Y T R U C K S H O P A A A N U A L HEATER RADIO R PO HORN Figure 4 4 Cob Engine and C h assis W irin g T V 7 0 Sheet 4 o f 6 CHASSIS ELECTRICAL AND INSTRUMEN...

Page 824: ...C C MKR LPS BODY BUILDERS 5 W 14 DK B L U E 12 DK B LU E 6 l2 B L U E SPARE i L H H EAD LP L H PARK LP CHEV ONLY l2 YELL L H DIR L P j f 1S S E M ITRL PLUG 5 T 7 WIRE R PO U 8 7 I2BR N TAIL LPS V y I2...

Page 825: ...ABLE ASM D IR E C T SW ASM TO IN STR P N L HARN CAB JCT BELOW FLOOR AT L H FRT STE P RISER U N D E R CAB AT CAB REAR IN S T R PANEL HARN TO H D LP 4 PARK LR HARN E N G HARN TO 3 T 0 P T A IL LP FRT E...

Page 826: ...V...

Page 827: ...made to assure that no looseness exists that could permit excessive vibration and shock loads Rubber cushions and rebound springs are subject to deterioration weakening andbreak age and should be rep...

Page 828: ...if attached to radiator 4 Remove fan shroud attaching bolts then lay shroud back over fan blade 5 Remove upper nut washer and insulator from each radiator stabilizer rod see fig 4 NOTE Do not move low...

Page 829: ...oils remove coils if necessary Disconnect oil cooler lines if equipped In addition remove power steering reservoir and receiver dehydrator if attached to radiator 6 Remove nuts w ashers and spring fro...

Page 830: ...ts retaining trunnion mounting brackets to frame Raise core slightly and remove trunnion type mounting bracket NOTE Radiator may not balance in an exact perpendicular manner with the lift hooks instal...

Page 831: ...in to permit installation of side fram es later 3 Position tank gasket on upper core flange then place upper tank on gasket and assem ble the reinforcing pieces to the underside of flange Loosely inst...

Page 832: ...sure to escape completely Then turn cap again slowly counterclockwise to remove NOTE A special testing kit for radiator filler caps can be obtained locally Instructions supplied with kit should be fol...

Page 833: ...em cools off 5 Do not pour cold water into cooling system when the engine is hot Wait until system cools off 6 If cooling system requires frequent refill ing check for leaks 7 Keep all connections tig...

Page 834: ...eal to prevent damage to lip of vane and also to seal cavity as theseparts may be read ily damaged CLEANING INSPECTION AND REPAIR Clean all components in a suitable solvent and dry with air pressure I...

Page 835: ...temperature of water gradually Shutterstat should close and at sam e tim e exhaust the outlet pressure to gauge at 180 F on all models except TV 70 and DC FC 90 with Cummins NT335 engine which should...

Page 836: ...control rod assem bly 18 is to be replaced do not reposition adjusting nuts 17 and leave control rod attached to bell crank 15 3 Remove nuts 10 from four bolts 2 which hold cylinder assem bly together...

Page 837: ...vehicle bring air pressure in system up to normal approximately 105 120 psi Check system for air leaks 5 Adjust air cylinder linkage if necessary NOTE The actual adjustment is made by re positioning...

Page 838: ...olant when hot will cause loss of coolant through overflow tube 4 Do not remove radiator filler cap when engine is hot Wait until system cools off 5 Do not pour cold water into cooling system when the...

Page 839: ...Remover and Replacer Radius Leaf Eye Bushing J 6 8 8 8 Valve Core Replacer J 8424 Overtravel Lever Piston Compressor SECTION 5A HYDRAULIC BRAKES J 4707 Adjusting Tool J 22348 Brake Spring Tool Tool No...

Page 840: ...cale J 8529 Thermometer J 21260 0 50 Ohm Variable R esistor J 23586 Poly V Belt Tension Gauge SECTION 6T AIR COMPRESSORS AND GOVERNORS J 23573 Belt Tension Gauge SECTION 7D CLUTCH CONTROLS J 8554 Mast...

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Chevrolet 70 Series 1970, Service Manual

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Summary of Contents for 70 Series 1970

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