Chevrolet 1980 Light Duty Truck Service Manual page 411

a. Check low oil pressure and/or insufficient oil supply
and correct as necessary.
b. Check for excessive bearing clearance and correct as
necessary.
c. Check for excessive crankshaft end play and correct
as necessary.
d. Check for eccentric or out-of-round crankshaft
journals and correct as necessary.
a. Check for broken valve springs and replace as
necessary.
b. Check for worn or sticking rocker arms and repair
or replace as necessary.
c. Check for worn or bent push rods and replace as
necessary.
d. Check for valve lifters incorrectly fitted to bore size
and correct as necessary.
e. Check faulty valve lifter plunger or push rod seat and
replace lifters as necessary.
f. Check for plungers excessively worn causing fast
leakdown under pressure and replace as necessary.
g. Check for excessively worn camshaft lobes and
a. Check for overadvanced ignition timing and/or
faulty ignition system and correct as necessary.
b. Check for loose or improper application of spark
plugs, or spark plugs with cracked or broken ceramic cores
and replace as necessary.
c. Check for the use of sub-standard fuel and correct
as necessary.
d. Check for foreign material in fuel lines and/or
carburetor and correct as necessary.
e. Check for restricted fuel delivery to carburetor
(pinched lines, faulty fuel tank cap or pick-up) and correct
as necessary.
f. Check fuel pump operation and replace if necessary.
g. Check EFE system operation and repair or replace
as necessary.
NOISY MAIN BEARINGS
e.
necessary.
f.
necessary.
NOISY VALVE LIFTERS
replace if necessary.
h. Check valve lifter oil feed holes plugged causing
internal breakdown and correct as necessary.
i. Check faulty valve lifter check ball, (nicked, flat spot,
or out of round) and replace as necessary.
j. Check rocker arm retaining nut to be installed upside
down and correct as necessary.
k. Check for end of push rod excessively worn or flaked
and replace as necessary.
ENGINE DETONATION
h. Check EGR system operation and correct as
necessary.
i. Check thermostatically controlled air cleaner
operation and correct as necessary.
j. Check P.C.V. system operation and correct as
necessary.
k. Check for vacuum leaks and repair or replace as
necessary.
1.
necessary.
m. Check for excessive combustion chamber deposits
and correct as necessary.
n. Check for leaking, sticking, or broken valves and
repair or replace as necessary.
ENGINE M ECHA NICAL
Check for excessive belt tension and adjust as
Check for loose torsional damper and replace as
Check engine operating temperature and correct as
6A-7
LIG H T T R U CK S ER V IC E M ANUAL