Chevrolet 1963 Corvette, Руководство по ремонту и настройке

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TROUBLESHOOTING 291
Section 9—Valve Train
See Chapter 3 for service procedures
Test and Procedure
Results and Indications
Proceed
to
9.1—Evaluate the valve train: Remove
the valve cover, and ensure that
the valves are adjusted to specifi-
cations. A mechanic's stethoscope
may be used to aid in the diagnosis
of the valve train. By pushing the
probe on or near push rods or
rockers, valve noise often can be
isolated. A timing light also may
be used to diagnose valve prob-
lems. Connect the light according
to manufacturer's recommen-
dations, and start the engine. Vary
the firing moment of the light by
increasing the engine speed (and
therefore the ignition advance),
and moving the trigger from cylin-
der to cylinder. Observe the
movement of each valve.
Sticking valves or erratic valve train motion See
can be observed with the timing light. The Chapter
cylinder head must be disassembled for re- 3
pairs.
9.2—Check the valve timing: Locate
top dead center of the No. 1 pis-
ton, and install a degree wheel or
tape on the crankshaft pulley or
damper with zero corresponding
to an index mark on the engine.
Rotate the crankshaft in its direc-
tion of rotation, and observe the
opening of the No. 1 cylinder in-
take valve. The opening should
correspond with the correct mark
on the degree wheel according to
specifications.
If the timing is not correct, the timing cover
must be removed for further investigation.
See
Chapter
3
Section 10—Exhaust System
Test arid Procedure Results arid Indications
Proceed
to
10.1—Determine whether the exhaust
manifold heat control valve is
operating: Operate the valve by
hand to determine whether it is
free to move. If the valve is free,
run the engine to operating tem-
perature and observe the action of
the valve, to ensure that it is open-
ing.
If the valve sticks, spray it with a suitable sol-
vent, open and close the valve to free it, and
retest. If the valve functions properly:
If the valve does not free, or does not op-
erate, replace the valve:
10.2
10.2
10.2—Ensure that there are no exhaust
restrictions: Visually inspect the
exhaust system for kinks, dents, or
crushing. Also note that gases are
flowing freely from the tailpipe at
all engine speeds, indicating no
restriction in -the muffler or reso-
nator.
Replace any damaged portion of the system:
11.1