Chevrolet 70 1969 Series, Shop Manual

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6V-53 DIESEL ENGINE 6C-4
IN JEC T IO N A N D G O V E R N O R S Y S T E M (6V-53
E N G IN E )."
POSITIONING IN J E C T O R C O N T R O L R A C K
Refer to " F U E L IN JEC T IO N A N D G O V E R N O R
S Y S T E M (6V-53 E N G IN E )" (SEC. 6M) for this
procedure.
O T H E R G O V E R N O R A D JU S T M E N T S
Governor high speed (no-load) spring adjust­
ment, low speed spring adjustment, and buffer
screw adjustment should be performed in sequence
mentioned, as directed under " F U E L IN JE C T IO N
A N D G O V E R N O R S Y S T E M (6V-53 E N G IN E )"(S E C .
6M) of this manual.
6V-53N DIESEL ENGINE TUNE-UP CHART
EN G IN E TYPE ............... 6V 53N (2 Stroke Cycle)
N U M B E R O F C Y L I N D E R S ................................. 6
C Y L IN D E R NUM BERING . . . . . (See Figure 2)
FIRING O R D E R .................. 1L-3R-3L-2R-2L-1R
V A L V E L A SH . . . . 0.024" (Hot) or 0.026" (Cold)
C Y L IN D E R H E A D BOLT
T O R Q U E ............................ 170-180 Ft.-Lbs.*
E N G IN E ID L E SPEED ......................... 500 Rpm
EN G IN E G O V E R N E D SPEED
Full Load ...................................... 2600 Rpm
No Load ......................................... 2750 Rpm
F U E L IN JE C T O R T Y P E ................................. N45
IN J E C T O R V A L V E OPENING
PRESSURE ......................................... 2600 Psi
C O M PR ESS ION R A T IO
21:1
C Y L IN D E R C O M P R E S S I O N .................. 540 Psi**
IN J E C T O R TIM IN G D I M E N S I O N .......... 1.460"***
F U E L SUPPLY PUMP
Capacity
(at 1500 Engine R p m ) . . . . 90 Gal. Per Hr.
Relief Valve Opens
(Max. Lbs. Pressure)...............................75
* Threads and bolt heads oiled.
** With engine running at 600 rpm. Variation between cylinders not to exceed 25 psi.
*** Use injector timing gauge No. J-1853.
IN-VEHICLE SERVICE OPERATIONS
(6V-53 DIESEL ENGINE)
GENERAL
This sub-section contains brief instructions
for replacing engine, and for making replacement
of engine components which can be made without
removing engine from chassis.
ENGINE REPLACEMENT
R E M O V A L
1. Drain cooling system.
2. Disconnect battery.
3. Disconnect accelerator control at pedal
shaft lever at rear of engine. This is necessary
to permit removal of engine access cover in cab.
4. Inside cab, remove floor mat, then remove
floor pan above transmission. Remove transmis­
sion gearshift lever.
5. Remove engine access cover from cab.
6. Disconnect light wiring harness. Remove
hood assembly, then remove grille brace bolts and
support bracket bolts. Remove grille assembly.
7. Disconnect radiator hoses, vent line, and
by-pass line. Remove radiator and support as­
sembly.
8. Remove front bumper.
9. Remove air cleaner and hoses.
10. Disconnect exhaust pipes from manifolds.
11. Disconnect engine wiring and disconnect
wiring and cables from starting motor terminals.
12. Disconnect fuel supply and return lines.
13. Detach clutch control cylinder from fly­
wheel housing. Disconnect tachometer drive shaft,
14. Disconnect air lines from air compressor.
N O T E : If desired, the air compressor may be
removed from engine prior to engine removal.
15. Attach overhead hoist to engine, then re­
move two front mounting bolts at crossmember.
Lift engine slightly to transfer engine weight to
hoist, then remove clutch housing-to-flywheel hous­
ing bolts. Move engine forward to disengage clutch
disc from transmission mainshaft, then lift engine
out of vehicle.
Figure 3 is view inside cab with engine cover
and transmission cover removed.
CHEVROLET SERIES 70-80 HEAVY DUTY TRUCK SHO P M ANUAL