Chevrolet 1963 Corvette, Руководство по ремонту и настройке

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122 ENGINE AND ENGINE REBUILDING
FLATTENED
GAGING PLASTIC
Check rod bearing clearance with Plastigage or
equivalent
TANG
Undersize marks are
stamped on the
bearing shells. The
tang fits in the notch
on the rod and cap
the crank journal,
and blow any oil
from the oil hole in
the crankshaft;
Plastigage®
lengthwise along
the bottom
center of the
lower bearing
shell, then install the cap with shell and
torque the bolt or nuts to specification.
DO
NOT turn the crankshaft with Plastigage®
in the bearing.
3. Remove the bearing cap with the shell.
The flattened Plastigage® will be found stick
ing to either the bearing shell or crank jour
nal.
Do not remove it yet.
4. Use the scale printed on the Plasti
gage® envelope to measure the flattened ma
terial at its widest point. The number within
the scale which most closely corresponds to
the width of the Plastigage® indicates bearing
clearance in thousandths of an inch.
5. Check the specifications chart in this
chapter for the desired clearance. It is advis-
able to install a new bearing if clearance ex-
ceeds .003 in.; however, if the bearing is in
good condition and is not being checked be-
cause of bearing noise, bearing replacement
is not necessary.
6. If you are installing new bearings, try a
standard size, then each undersize in order
until one is found that is within the specified
limits when checked for clearance with Plas
tigage®. Each undersize shell has its size
stamped on it.
7. When the proper size shell is found,
clean off the Plastigage®, oil the bearing thor
oughly, reinstall the cap with its shell and
torque the rod bolt nuts to specification.
NOTE: With the proper bearing selected
and the nuts torqued, it should be possible
to move the connecting rod back and forth
freely on the crank jorunal as allowed by
the specified connecting rod end clearance.
If the rod cannot be moved, either the rod
bearing is too far undersize or the rod is
misaligned.
PISTON AND CONNECTING ROD
ASSEMBLY AND INSTALLATION
Install the connecting rod to the piston, mak-
ing sure piston installation notches and any
marks on the rod are in proper relation to one
another. Lubricate the wrist pin with clean
engine oil, and install the pin into the rod
and piston assembly, either by hand or by us-
ing a wrist pin press as required. Install snap
rings if equipped, and rotate them in their
grooves to make sure they are seated. To in-
stall the piston and connecting rod assembly:
1. Make sure connecting rod big-end
bearings (including end cap) are of the cor
rect size and properly installed.
2. Fit rubber hoses over the connecting rod
bolts to protect the crankshaft journals, as in
UNDERSIZE STAMP
IN THOUSANDS
RING COMPRESSOR
Install piston ring compressor, then tap the piston
into the cylinder bore carefully. Make sure the pis-
ton front marks are correctly positioned when in-
stalling