Chevrolet Light Duty Truck 1973 Service Manual page 372

6 3 6 E N G IN E
holes with Tool J-22808-2 and then finish reaming
them with Tool J-22808-1 (fig. 31L).
5. Install oversize dowel pins flush with flywheel
retaining bolt surface.
6. Install rear main bearing cap and torque bolts to
specifications. Install oil pan with new gaskets and
seals. Torque oil pan retaining screws to
specifications.
Engine Mounts
Engine mounts (fig. 32L-38L) are the non-adjustable
type and seldom require service. Broken or deteriorated
mounts should be replaced immediately, because of the
added strain placed on other mounts and drive line
components.
Checking Engine Mounts
Front Mount
Raise the engine to remove weight from the mounts and
to place a slight tension in the rubber. Observe both
mounts while raising engine. If an engine mount
exhibits:
a. Hard rubber surface covered with heat check
cracks;
b. Rubber separated from a metal plate of the
mount; or
c. Rubber split through center.
Replace the mount, if there is relative movement
between a metal plate of the mount and its attaching
points, lower the engine on the mounts and tighten the
screws or nuts attaching the mount to the engine, frame,
or bracket.
Rear Mount
Raise the vehicle on a hoist. Push up and pull down on
the transmission tailshaft while observing the transmis­
sion mount. If the rubber separates from the metal plate
of the mount or if the tailshaft moves up but not down
(mount bottomed out) replace the mount. If there is
relative movement betwen a metal plate of the mount
and its attaching point, tighten the screws or nuts
attaching the mount to the transmission or crossmember.
Front Mount Replacement
C, K and P Series
1. Remove frame bracket to mount bolt.
2. Raise engine enough to clear mount.
3. Remove mount and install new mount.
4. Install new mount and torque bolts to specifications.
5. Lower engine then install frame bracket to mount
bolt and torque to specifications.
G Series
1. Raise vehicle on hoist.
2. On manual transmission equipped vehicles.
a. Disconnect clutch rod at outboard lever on
clutch cross shaft.
b. Remove the two bolts securing clutch cross shaft
bracket to frame side rail, and position clutch
linkage away from engine mount.
3. Remove mount-to-bracket through-bolt.
Raise engine sufficiently to clear mount. Remove
4.
bolts securing mount to frame bracket.
5. Install new mount to frame bracket, and torque
bolts to specifications.
6. Lower engine to align mount with engine bracket.
Install through bolt and torque to specifications.
7. On manual transmission equipped vehicles.
a. Position clutch cross shaft between frame side
rail and ball stud on engine bracket. Install and
torque frame bolts.
b. Connect clutch rod at outboard lever on clutch
cross shaft.
8. Lower vehicle on hoist and check operation of
clutch.
Rear Mount Replacement
C, K and P Series
1. Raise and support vehicle.
2. Bend mount bolt french lock tabs away from bolt
head, then remove mount bolts, lower mount and
spacer.
3. Raise engine enough to clear upper mount
assembly and remove upper mount from frame
member.
NOTE: On models using a propeller shaft
brake of any type, it is necessary to remove
screws from transmission hole cover to allow
the engine to raise because of the limited
clearance between the brake and transmis­
sion hole cover.
Place new upper mount in place on frame member,
4.
then lower engine to within
5. Align mount so that guide dowel enters hole in
mount, install bolt through french lock, lower
mount and spacer, then install bolt up through
frame, upper mount and thread into engine bell
housing loosely.
6. Lower engine completely and tighten mount bolt,
then bend tabs of french lock to lock the bolt in
place.
G Series
1. Raise vehicle on hoist and support transmission so
as not to interfere with support crossmember
removal.
2. Remove bolts securing rear mount to support
crossmember.
3. Remove support crossmember retaining bolts from
inch of mount.
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LIGHT DUTY TRUCK SERVICE MANUAL