Remove And Replace - Pontiac tempest 1968 Service Manual

V-8 E N G I N E 6-63
Fig. 6-110 Measuring Plastigage
journal or bearing surface. Install the cap and tighten
cap bolts to proper torque.
NOTE; Do not turn crankshaft with Plastigage in
place.
3. Remove bearing cap and using Plastigage scale
on envelope (Fig. 6-110), measure width of com­
pressed Plastigage before removing i t from the
bearing or journal. I f the bearing clearance is be­
tween .0002" and .0020", the clearance Is satis­
factory. If the clearance is more than .0020", replace
the bearing with the next size undersize bearing and
recheck clearance. Bearings are available i n stan­
dard size, .001" and .002" undersize.
4. Install a new rear main bearing o i l seal In the
cylinder block and main bearing cap i f the rear main
bearing was checked and/or replaced.
5. Replace o i l pump, cylinder block to o i l baffle
tube, and o i l baffle i f they were previously removed.
6. Replace o i l pan, using new gaskets.
CONNECTING ROD BEARINGS-
REMOVE AND REPLACE
1. Remove o i l pan (see Oil Pan - Remove and
Replace).
• 2. To gain access to numbers 5, 6, 7 or 8 con­
necting rod caps i t w i l l be necessary to remove o i l
pump screen and o i l baffle. Pump must be removed
as an assembly. Screen tube Is a press f i t In pump
tody and must not be rotated or removed.
3. Rotate crankshaft as necessary to bring crank
N O . 1 N O . 2 C O N N E C T I N G
C O N N E C T I N G R O D CAP
R O D C A P /
V /
F i g . 6-111 Crankshaft Positioned For Removal of
No. 1 and N o . 2 Connecting Rod Caps
pin carrying bearing to be replaced straight down
(Fig. 6-111).
4. Remove bearing cap of bearing to be replaced.
5. Install connecting rod bolt guide set J 5239 on
connecting rod bolts (Fig. 6-113).
6. Push piston and rod assembly up far enough to
allow removal of bearing shell. Remove bearing
shells f r o m rod and cap.
7. Inspect crank pin for damage, out-of-round, and
taper.
8. Reassemble cap and rod with new bearing shells
and check f i t , using Plastigage as outlined below.
CA UTION; Under no circumstances should a bear­
ing cap be filed or shimmed in an effort to affect
a fit.
NOTE; In 1968, a number of 2 bbl. equipped V-8's
will have .010'[undersize crankpins. These crank­
shafts may be identified by a .010" U.S. stamp on
the front of the No. 1 counterweight and the rear of
No. 8 counterweight. A check should be made for
this undersize crankshaft before replacing rod
bearings.
PLASTIGAGE METHOD FOR DETERMINING
CONNECTING ROD BEARING CLEARANCE
1. Remove the cap of the bearing to be checked.
Wipe the bearing and the crankpin free of o i l .
2. Place a piece of type P G - l Plastigage the length
of the bearing (parallel to the crankshaft) on the
crankpin or bearing surface. Install the cap and
tighten cap bolts to 43 l b . f t .
NOTE; Do not turn crankshaft with Plastigage in
place.
3. Remove bearing cap and using Plastigage scale
on envelope (Fig. 6-110) measure width of com­
pressed Plastigage before removing i t f r o m the