Chevrolet 1963 Corvette, Руководство по ремонту и настройке

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ENGINE AND ENGINE REBUILDING 121
3ROOVE Measure
piston ring side clearance with feeler gauge
cleaned. Slide a piston ring into its groove,
and check the side clearance with a feeler
gauge. Make sure the feeler gauge is inserted
between the ring and its lower land (lower
edge of the groove), because any wear that
occurs forms a step at the inner portion of the
lower land. If the piston grooves have worn
to the extent that relatively high steps exist
on the lower land, the piston should be re-
placed, because these will interfere with the
operation of the new rings and ring clear-
ances will be excessive. Piston rings are not
furnished in oversize widths to compensate
for ring groove wear.
Install the rings on the piston, lowest ring
first, using a piston ring expander. There is a
high risk of breaking or distorting the rings,
or scratching the piston, if the rings are in-
stalled by hand or other means.
Position the rings on the piston as illus-
ENQINE LEFT ENGINE FRONT ENGINE RIGHT
"SMALL V8"
"A" OIL RING SPACER SAP (Tang In
Hole or Slot within Arc)
"B" OIL RING RAIL GAPS "C" 2ND
COMPRESSION RING CAP "D" TOP
COMPRESSION RING GAP Piston ring gap
location—all engines
trated; spacing of the various piston ring gaps
is crucial to proper oil retention and even
cylinder wear.
When installing new rings,
refer to the installation diagram furnished with
the new parts.
Connecting Rod Bearings
Conecting rod bearings for the engines cov-
ered in this guide consist of two halves or shells
which are interchangable in the rod and cap.
When the shells are placed in position, the
ends extend slightly beyond the rod and cap
surfaces so that when the rod bolts are torqued
the shells will be clamped tightly in place to
insure positive seating and to prevent turn-
ing. A tang holds the shells in place.
NOTE: The ends of the bearing shells must
never be filed flush with the mating surface
of the rod and cap.
If a rod bearing becomes noisy or is worn
so that its clearance on the crank journal is
excessive, a new bearing of the correct un-
dersize must be selected and installed since
there is no provision for adjustment.
CAUTION: Under no circumstances should
the rod end or cap be filed to adjust the
bearing clearance, nor should shims of any
kind be used.
Inspect the rod bearings while the rod as-
semblies are out of the engine. If the shells
are scored or show flaking, they should be
replaced. If they are in good shape check for
proper clearance on the crank journal (see
below). Any scoring or ridges on the crank
journal means the crankshaft must be re-
placed, or reground and fitted with under-
sized bearings.
NOTE: If journals are deeply scored or
ridged the crankshaft must be replaced, as
regrinding will reduce the durability of the
crankshaft.
ROD BEARING INSPECTION AND
REPLACEMENT
NOTE: Make sure connecting rods and their
caps are kept together, and that the caps
are installed in the proper direction.
Replacement bearings are available in
standard size, and in undersizes for reground
crankshafts. Connecting rod-to-crankshaft
bearing clearance is checked using Plasti-
gage® at either the top or bottom of each crank
journal. The Plastigage® has a range of .001
in. to .003.
1. Remove the rod cap with the bearing
shell. Completely clean the bearing shell and
PISTON RING
FEELER GAUGE
2-4-6-i cyl.
1-3-5-7 cyl.