Chevrolet 10 Series 1970 Service Manual page 323

Engine Tune-Up ......................................................... ........................
Engine Mechanical (In L i n e ) ..............................................................
General D es crip tio 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
Test C om p res sion ...................................................................................... 6-1
Service and Install Spark P lu g s ....................................................... ........ 6-2
Service Ignition System .................................................................. ........ 6-2
Service Battery and Battery C a b le s ......................................................... 6-4
Service D elcotron and Regulator ................................................... ........ 6-5
Service B e lt s ...................................................................................... ........ 6-5
Service M anifold Heat V a l v e .................................................................... 6-5
Tighten M a n if o ld ...................................................................................... 6-5
Service Fuel Lines and Fuel F ilter ..........................................................
Service C ooling System ...........................................................................
Check and Adjust A ccelerator L in k a g e .......................................... .........
Service Crankcase Ventilation ....................................................... .........
Service A ir Injection Reactor S y s te m ............................................ .........6-7
The engine tune-up is im portant to the modern auto­
m otive engine with its va stly im proved pow er and p e r ­
form an ce. The higher com pression
e le c tr ic a l system s and other advances in design, make
today' s engines m ore sen sitive and have a decided effect
on pow er, p erform an ce and fuel consumption.
It is seldom advisable to attem pt a tune up by c o rrectio n
o f one o r two item s only. T im e w ill norm ally be saved
and m ore lasting resu lts assured i f the technician w ill
fo llo w a definite and thorough procedure o f analysis and
c o rrec tio n o f a ll item s affectin g pow er, p erform an ce
and econom y.
Tne tune-up w ill be p erfo rm ed in two parts. The fir s t
part w ill consist o f m echanical checks and adjustments;
the second part w ill consist o f an instrument checkout
that can be p erform ed with any one o f the units o f s e rv ic e
MECHANICAL CHECKS AND ADJUSTMENTS
Spark Plug Removal
Rem ove any fo reig n m atter from around spark plugs
by blowing out with com p ressed a ir, then disconnect
w ir e s and rem ove plugs.
SECTION 6
ENGINE
CONTENTS OF THIS SECTION
6-1 Engine Mechanical ( V
6-13 Special T o o l s .........................................................................................
ENGINE TUNE-UP
INDEX
Page
Choke A d ju s tm e n t........................................................................... ..... 6-7
Instrument C h eck -O u t......................................................................... ......6-7
Instrument Hook-Up .............................................................................6-7
Check and Adjust D w e l l .................................................................. ......6-7
Check D w ell V a r ia t io n .................................................................... ......
Check and Adjust T i m i n g ................................................................ ......
Adjust Idle Speed and M ix t u r e ....................................................... ......
A ddition al Checks and A d ju s tm e n ts ................................................ ......6-10
Testing Crankcase V en tilation V alve
Cylinder Balance T e s t .............................................................................6-10
B a t t e r y ............................................................................................... ...... 6-10
6-6
Ignition
6-6
C a r b u r e t o r ........................................................................................ ...... 6-11
6-6
Fuel P u m p ........................................................................................ ...... 6-11
6-6
C ooling S y s t e m .................................................................................... ...... 6-11
Cylinder Head Torqu e and V alve Adjustm ent
GENERAL DESCRIPTION
equipment available fo r this purpose. A lw ays follow the
instructions provided by the m anufacturer o f the p a r ­
ra tios, im proved ticu lar equipment to be used.
Additional checks and adjustments a re included in the
la tte r part o f this section fo r use as requ ired. Many o f
these
trouble
a re uncovered requ irin g m ajor c o r r e c tiv e action, r e fe r
to the appropriate section o f this manual o r the C hassis
Overhaul Manual fo r detailed s e rv ic e inform ation.
T y p ica l illu stration s and procedu res are used except
w here sp ec ific illu stration s o r procedu res a re n ecessary
to
operations
operations can be p e rfo rm e d on the veh icle.
Test Compression (Fig. 1)
The com pression check is im portant because an engine
with low o r uneven com pression cannot be tuned su ccess­
fu lly.
rected b e fo re proceedin g with the engine tune up.
8
) .....................................................................
................................................................................................... 6-10
operations can be used to isolate and c o r r e c t
located during the tune-up.
c la r ify the operation. Illu stration s showing bench
a re used fo r c la rifica tio n s,
It is essen tial that im p ro p er com pression be c o r­
Page
6-25
6-38
Page
6-8
6-8
6-8
............................................ ......6-10
................................... 6-12
W here conditions
h ow ever, a ll
CHEVROLET TRUCK SERVICE MANUAL