GMC 4000 Series Service Manual page 266

Subject
General Information
Engine L u b r ic a tio n ..............................................................................
Engine Maintenance and Tune-up
Tune-up, Checks, and Adjustments
In-Line Engine R e p la c e m e n t.............................................................
V6 Engine Replacement
In-Vehicle Service Operations (In-Line Engine)
In-Vehicle Service Operations (V6 Engines)
Trouble Diagnosis Chart
Torque Wrench Specifications
TRUCK SERIES
LA, LV4000
EM4500
ES4500
PS4500
EM5500
GENERAL INFORMATION
A definite, system atic maintenance program is
required to assure satisfactory economical per­
formance of engine. Included in maintenance pro­
gram must be the servicing of related units and
system s as well as regular tune-up of engine.
Frequency of tune-up is dependent upon the
type of service in which the vehicle is used.
This section of manual provides instructions
for servicing the various item s and tuning the en­
gine. Unless otherwise stated, the procedures are
applicable to all gasoline engines used in vehicles
covered by this manual. To adequately accomplish
a satisfactory tune-up, reliable test equipment in
the hands of trained personnel is necessary.
ENGINE LUBRICATION
IN-LINE ENGINES
Lubrication system for In-line engines is
shown in figure 1. After passing through full-flow
oil filter, oil is supplied under pressure to main
oil gallery where it is distributed to main bearings,
and crankshaft drillings. Hydraulic valve lifters
receive oil from main gallery. Oil metered from
G M C S E R V I C E M A N U A L
SECTION 6A
Q a f a l i n e
Contents of this section are listed in Index below:
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ENGINE APPLICATION CHART
GMC ENGINE
STANDARD OPT.
305C 351C
305E
—
250 292
250 292
305C 351C
..................................................
..............................................
......................
.............................
TRUCK SERIES
SM5500
ES5500
SS5500
EM6500
SM6500
valve lifters p asses through hollow push rods to
lubricate individually-mounted rocker arms.
V6 ENGINES
Lubrication of V6 engines is typically illu s­
trated in diagram shown in figure 2.
High capacity type oil pump (9, fig. 2) delivers
oil to main oil gallery in cylinder block after oil
Sec. 6A
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GMC ENGINE
STANDARD OPT.
305C 351C
292
- -
292
- -
305C 351C
351M
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