BRAKES 5-74
tw o-w ay con trol va lve a re used in combination on some
ve h ic le s as shown in F ig. 124. Th is combination p erm its
fu ll brake va lve d e liv e r y p ressu re to the front brakes
when on dry roads, o r at the option o f the d r iv e r , lim its
the p ressu re to the fron t brakes to 50 p ercen t o f the
brake va lve d e liv e r y p ressu re when on slip p ery roads.
The tw o-w ay con trol va lve is mounted on the instru
ment panel within easy reach o f the d r iv e r . The lim itin g
quick re le a s e va lv e is mounted on fra m e crossm em b er
near the fron t brake cham bers. One a ir line fro m brake
application va lve is connected to the in let p o rt o f the
tw o-w ay va lve and another connects to the brake valve
p o rt at top o f lim itin g quick re le a s e v a lv e . Another a ir
line connects the side d e liv e ry p ort o f the tw o-w ay valve
to the p ort opposite the mounting pad o f the lim itin g quick
re le a s e va lv e . The two other side ports o f the lim itin g
quick re le a s e va lve a re connected to the fron t brake
cham bers.
The lim itin g quick r e le a s e v a lv e , b esides providin g
fo r a 50 percen t reduction o f fron t wheel brake p ressu re,
also s e rv e s as a quick re le a s e v a lv e when brakes are
relea sed .
T w o -W a y V a lv e Replacem ent
Removal
1. B lo c k v e h ic le w h 'eels.
2. Drain a ir p ressu re fro m brake system .
3. Disconnect a ir lin es.
4. Rem ove screw s which fasten plate and valve to in
strum ent panel. Rem ove plate and v a lve. F o r o v e r
haul,
r e fe r
to
'-D iffe re n tia l Control V a lv e ” in
“ R E A R A X L E ” (Sec. 4) o f this manual.
Installation
1. P osition va lve in instrum ent panel and connect a ir
lines.
2. Fasten va lve and plate to instrum ent panel.
3. Start engine and build up a ir p ressu re to operating
le v e l.
4„ Check fo r leaks. Check operation o f brakes.
Limiting V a lv e Replacement
Removal
1. Block veh icle wheels,,
2. Drain a ir fro m brake system ,
3. D isconnect a ir lin es.
4. R em ove bolts which fasten va lve to ve h ic le . Rem ove
v a lve.
Disassembly
1. Clamp mounting bracket in v is e having protected
jaw s.
2. Rem ove end cap and gasket.
3. Rem ove piston assem bly fro m body.
4. Hold exhaust va lve, rem o ve nut inlet va lve and spring
fro m piston.
5. R em ove “ O ” rings.
Cleaning and Inspection
Wash a ll m etal parts in m in eral sp irits o r cleaning
solvent. Examine exhaust v a lv e seat in end cap and inlet
va lve seat in piston. They must be fr e e o f nicks. E xa
mine inlet and exhaust v a lv e s , they must be smooth and
fr e e of nicks. Exam ine piston b ore in body; b ore must
be smooth.
Assembly
1. In stall spring on exhaust va lve stem position in cage,
in stall in let va lve on stem with nut. Tighten secu rely.
2. In stall new “ O ” rings and in sert, lu bricate piston
and in sert assem bly in body.
3. Install gasket and end cap. Tighten cap secu rely.
Installation
1. Connect a ir lines.
2. P osition va lve on veh icle and fasten with bolts.
3. Start engine and build up a ir p ressu re to operating
le v e l.
4. Check fo r leaks.
5. Check operation o f brakes.
Test
Apply a ir p ressu re to both brake v a lv e p o rt and control
p ort; no leak allow ed at the exhaust port. Disconnect
con trol port p ressu re supply; no leak allow ed at control
p ort o r exhaust port.
PUSH-PULL CONTRO L VALVE (Fig. 1 2 6 )
A manual em ergen cy application o r parking application
can be made by operating the manual con trol on the in
strum ent panel. R elease can be made manually, provided
there is at lea st 80 pounds p ressu re in the em ergency
a ir system . This va lve con trols the tra cto r o r main unit
only.
Removal
1. B lock o r hold veh icle by means other than a ir and
drain a ir system .
2. Disconnect a ir lin es fro m control va lve.
3. R em ove control va lve mounting nut and rem ove
va lve.
Disassembly
1. To replace seals, rem ove the va lve cap and gasket.
2. Rem ove the va lve stem nut and rem ove the piston.
3. Pu ll the va lve stem from the body.
Cleaning and Inspection
Wash a ll m etal p arts in a good cleaning solvent and
wipe dry. Wipe a ll reuseable rubber p arts with a cloth.
Replace any damaged seals o r p arts. Lubricate a ll parts
b efo re reassem bly.
Assembly
F o llo w disassem bly in re v e r s e o rd er.
CHEVROLET TRUCK SERVICE MANUAL
Содержание 10 Series 1970
Страница 1: ......
Страница 38: ...HEATER AND AIR CONDITIONING 1A 8 CHEVROLET TRUCK SERVICE MANUAL...
Страница 57: ...HEATER AND AIR CONDITIONING 1A 27 Fig 35 Compressor M ountings CHEVROLET TRUCK SERVICE MANUAL...
Страница 75: ...HEATER AND AIR CONDITIONING 1A 45 Fig 65 R oof M ounted System W iring Diagram CHEVROLET TRUCK SERVICE MANUAL...
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Страница 101: ...BODY IB 23 s A ADJUSTER SCREW AND LEVER ASSY Fig 5 9 Exploded V iew o f Level Ride Seat CHEVROLET TRUCK SERVICE MANUAL...
Страница 137: ...BODY IB 59 VIEW IN DIRECTION OF ARROW A Fig 137 A u x ilia ry Seat CHEVROLET TRUCK SERVICE MANUAL...
Страница 142: ...CHEVROLET TRUCK SERVICE MANUAL Fig 5 10 30 Series Truck Frame FRAME 2 4...
Страница 145: ...CHEVROLET TRUCK SERVICE MANUAL FRAME 2 7...
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Страница 228: ...REAR SUSPENSION AND DRIVE LINE 4 52 I Fig 88 Forward Rear A xle Assembly Exploded V iew CHEVROLET TRUCK SERVICE MANUAL...
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Страница 383: ...ENGINE FUEL 6M 19 F ig I t Engine Fuel S p ecial Tools CHEVROLET TRUCK SERVICE MANUAL...
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Страница 432: ...Fig 1 C lu tch Linkage Except P 2 0 4 0 Series...
Страница 433: ...CLUTCHES AND TRANSMISSIONS 7 3 Fig 2 C lutch Linkage Step Van P 20 40 Series CHEVROLET TRUCK SERVICE MANUAL...
Страница 506: ...FUEL TANK AND EXHAUST SYSTEMS 8 8 Fig 10 Vent Lines Cab M ounted Tanks CHEVROLET TRUCK SERVICE MANUAL...
Страница 528: ...Fig 31 T yp ica l Power Steering Hose Routings...
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Страница 566: ...ELECTRICAL BODY AND CHASSIS 12 4 Fig 3 Front Lighting Assemblies CHEVROLET TRUCK SERVICE MANUAL...
Страница 567: ...ELECTRICAL BODY AND CHASSIS 12 5 Fig 4 C learance and Id e n tific a tio n Lamps CHEVROLET TRUCK SERVICE MANUAL...
Страница 568: ...ELECTRICAL BODY AND CHASSIS 12 6 Fig 5 Rear Lighting Composite CHEVROLET TRUCK SERVICE MANUAL...
Страница 597: ...ELECTRICAL BODY AND CHASSIS 12 35 Fig 37 Engine Com partm ent CE M E60 CHEVROLET TRUCK SERVICE MANUAL...
Страница 598: ...ELECTRICAL BODY AND CHASSIS 12 36 TO FRAME i f Fig 38 Engine Com partm ent C D 50 CHEVROLET TRUCK SERVICE MANUAL...
Страница 608: ...ELECTRICAL BODY AND CHASSIS 12 46 Fig 48 Instrument Panel C A40 CE CS ME50 Exc 02 CHEVROLET TRUCK SERVICE MANUAL...
Страница 610: ...ELECTRICAL BODY AND CHASSIS 12 48 Fig 50 Instrument Panel CE M E60 03 13 CHEVROLET TRUCK SERVICE MANUAL...
Страница 614: ...ELECTRICAL BODY AND CHASSIS 12 52 Fig 54 Instrument Panel SA40 50 CHEVROLET TRUCK SERVICE MANUAL...
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Страница 649: ...SPECIFICATIONS 9 ENGINE SECTION 6 CHEVROLET TRUCK SERVICE MANUAL...
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