Chevrolet 1977 light duty truck, Руководство по обслуживанию

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d. Check, inspect an d regap spark plugs. Replace
as necessary.
e. Check distributor spark advance m echanism for
p ro p er operation. R e p a ir or replace as necessary.
f. Inspect exhaust system for restrictions. Correct
as necessary.
g. Check c a rb u re to r m ou n tin g gasket for air leaks.
R ep air as necessary.
h. Check and adjust valve lash.
i. Check for burned, w arped or sticking valves.
R ep air or replace as necessary.
j. Check engine for low compression. R ep air as
necessary.
k. Check engine operating tem perature. Correct as
necessary.
1. Check for loose, corroded or leaking wiring
connections (hulk-head connectors, etc.). R ep air as
necessary.
m. Check operation o f exhaust gas recirculation
system. R e p a ir or replace as necessary.
n. Check fuel system for leaks a n d / o r obstructions.
R e p a ir as necessary.
o. Check for vacuum leaks. Correct as necessary,
p. Check operation o f E FE valve as outlined in
Section 6E o f this manual. R e p a ir or replace as
necessary.
ENGINE HAS LOW POWER
a. Check for weak or faulty H.E.I. system coil as
outlined in Section 6D o f this manual.
b. Check ignition timing. Correct as necessary.
c. Check fo r excessive play in distributor shaft.
R e p a ir or replace as necessary.
d. Check, inspect and regap spark plugs. Replace
as necessary.
e. Check carb u re to r for incorrect a n d / o r misad-
ju sted idle speed, float level, leaking needle and seat, air
valve an d sticking choke or enrichm ent system. Adjust,
r e p a ir or replace as necessary.
f. Inspect c a rb u re to r fuel filter for presence o f
w ater a n d / o r im purities. Correct as necessary.
g. Check fuel p u m p fo r leaks an d p ro p e r
operation. Correct as necessary.
h. Check for sticking valves, weak valve springs,
incorrect valve timing, lifter noise and worn cam shaft
lobes. Adjust, r e p a ir or replace as necessary.
i. Check for excessive piston to bore clearance.
Correct as necessary.
j. Check c o n d itio n o f cylinders for uneven
compression a n d / o r blown head gasket. R ep air as
necessary.
valve k. Check pow er steering flow control
operation. R e p a ir or replace as necessary.
1. Check for clutch slippage (vehicles with m anual
transmissions) and adjust or replace as necessary.
m. Check hydraulic brake system for proper
operation. Correct as necessary.
n. Check engine operatin g tem perature. Correct as
necessary.
o. Check pressure r e g u la to r valve (au to m a tic
transmission) for proper operation. R e p a ir as necessary.
p. Check transmission fluid level. Correct as
necessary.
q. Loss o f power m ay be caused by using sub­
standard fuel. Correct as necessary.
r. Check operation o f EFE valve as outlined in
Section 6F. o f this manual. R ep air or replace as
necessary.
s. Check o p e r a tio n o f d iv e rte r valve (A.I.R.
system). R epair or replace as necessary.
t. Check for engine vacuum leaks. Correct as
necessary.
ENGINE DIESELING ON SHUT OFF
a. Check base idle speed for im p ro p er adjustm ent
an d correct as necessary.
b. Check ignition tim ing and reset to specifications
if required.
c. Check idle mixture setting an d correct as
necessary.
d. Check accelerator and choke linkage operation
and correct as necessary.
e. Check engine operating tem p eratu re and correct
as necessary.
f. Check therm ae valve for sticking and correct as
necessary.
ENGINE DETONATION
a. Check fo r overadvanced ignition tim ing a n d / o r
faulty ignition system an d correct as necessary.
b. Check for loose or im p ro p er application of
spark plugs, or spark plugs with cracked or broken
ceramic cores a n d replace as necessary.
c. Check for the use o f sub-standard fuel and
correct as necessary.
d. Check for foreign m aterial in fuel lines a n d / o r
c a rb u re to r 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 p u m p operatio n and replace if
necessary.
g. Check EFE system operatio n and rep air or
replace as necessary.
h. Check E G R system o peration and correct as
necessary.