Chevrolet 10 Series 1968, Руководство по обслуживанию

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SECTION 6
ENGINE
CONTENTS OF THIS SECTION
Gasoline E n g in e s .......................................................................6-1
Engine Tune Up ................................................................ ...6-1
Engine Mechanical (In L i n e ) ............................................. ...6-11
Engine Mechanical ( V 8 ) .......................................................6-25
Specifications
Special Tools
Page
At Rear of Manual
.................... 6-41
GASOLINE ENGINES
ENGINE TUNE-UP
INDEX
Page
General D e s c r ip t io n ............................................................. 6-1
Mechanical Checks and A d ju s tm e n ts ................................ 6-1
Spark Plug R e m o v a l .......................................................... 6-1
T est C o m p r e s s io n ............................................................. 6-1
Service and Install Spark Plugs .................................... 6-2
Service Ignition S y s t e m .................................................... 6-2
Service Battery and Battery Cables ............................. 6-4
Service Delcotron and R e g u l a t o r ................................... 6-4
Service Fan B e l t ................................................................ 6-4
Service Manifold Heat Valve . . . . ................................ 6-5
Tighten M a n if o ld ................................................................ 6-5
Service Fuel Lines and Fuel F ilte r ............................. 6-5
Service Cooling S y s t e m ................................................... 6-5
Check and Adjust A ccelera to r L in k a g e .......................... 6-5
Service Crankcase V e n tila tio n .......................................... 6-5
Service A ir Injection R eactor System .......................... 6-5
Adjust C h o k e ....................................................................... 6-5
Page
Instrument C h e c k - O u t .......................................................... 6-6
Instrument H o o k - U p .......................................................... 6-6
Check and Adjust D w e l l ................................................... g-6
Check Dwell Variation ................................................... g-6
Check and Adjust T i m i n g ................................................ 6-6
Adjust Idle Speed and Mixture ....................................... 6-7
Additional Checks and A d ju s tm e n ts ................................... 6-7
Testing Crankcase Ventilation V a l v e ............................. 6-7
Testing Cranking V o l t a g e ................................................ 6-7
Cylinder Balance T e s t ....................................................... 6-8
B a t t e r y ................................................................................ 6-8
Ignition . .............................................................................. 6-8
C a r b u r e t o r .......................................................................... 6-9
Fuel P u m p .......................................................................... 6-9
Cooling S y s t e m .................................................................... 6-9
Cylinder Head Torque and V alve A d ju s t m e n t ............. 6-9
I
GENERAL DESCRIPTION
The engine tune up is important to the modern auto­
motive engine with its vastly improved power and per­
formance.
The higher compression ratios, improved
electrical systems and other advances in design, make
today's engines more sensitive and have a decided effect
on power, performance and fuel consumption.
It is seldom advisable to attempt a tune up by correction
of one or two items only. Time w ill normally be saved
and more lasting results assured if the technician will
follow a definite and thorough procedure of analysis and
correction of all items affecting power, performance
and economy.
The tune up will be performed in two parts. The first
part will consist of mechanical checks and adjustments;
the second part will consist of an instrument checkout
that can be performed with any one of the units of service
equipment available for this purpose. Always follow the
instructions provided by the manufacturer of the par­
ticular equipment to be used.
Additional checks and adjustments are included in the
latter part of this section for use as required. Many of
these operations can be used to isolate and correct
trouble located during the tune up.
Where conditions
are uncovered requiring major corrective action, refer
to the appropriate section of this
manual or the
Truck Chassis Overhaul Manual for detailed service
information.
Typical illustrations and procedures are used except
where specific illustrations or procedures are necessary
to clarify the operation.
Illustrations showing bench
operations are used for clarifications, however, all
operations can be performed on the vehicle.
MECHANICAL CHECKS AND ADJUSTMENTS
Spark Plug Removal
Remove any foreign matter from around spark plugs
by blowing out with compressed air, then disconnect
wires and remove plugs.
Test Compression (Fig. 1)
The compression check is important because an engine
with low or uneven compression cannot be tuned success­
fully. It is essential that improper compression be cor­
rected before proceeding with the engine tune up.
CHEVROLET TRUCK SERVICE MANUAL