6 - 6 4
1968 P O N T I A C SERVICE M A N U A L
RIDGE CAUSED BY CYLINDER WEAR
F i g . 6-112
Cylinder Ring Ridge
crankpin or bearing. If the bearing clearance Is
between .0005" and .0025", the clearance is satis
factory. If clearance is more than .0025", replace
bearing with the next size undersize bearing and
recheck clearance. Bearings are available i n .001"
and .002" undersize.
4. R o t a t e the c r a n k s h a f t a f t e r b e a r i n g adjustment
to be sure bearings are not tight.
CONNECTING
ROD AND
PISTON
ASSEMBLY-
REMOVE
AND
REPLACE
REMOVE
1. Remove o i l pan, o i l baffle and o i l pump (see
Oil Pan - Remove - and Replace).
2. Remove intake manifold and cylinder head on
bank f r o m which piston is to be removed.
3. Rotate crankshaft so crankpin carrying assem
bly to be replaced projects straight downward ( F i g .
6-111).
4. Remove ring ridge (Fig. 6-112) using suitable
ring ridge remover.
5. Remove bearing cap and install connecting rod
bolt guide set J 5239.
6. Carefully remove
connecting
rod and piston
assembly by pushing out with knurled handle of long
guide (Fig. 6-113).
REPLACE
1. Install connecting rod bolt guide set on con
necting rod bolts with long handle guide on same
side as o i l groove in rod.
2. Using J 6647 or J 5684 (Fig. 6-114) ring com
pressor, insert piston and connecting rod assembly
Into cylinder so that notch in top of piston is toward
front of engine. Be certain o i l spurt hole (Fig. 6-121)
in connecting rod is toward camshaft.
J-5239
F i g . 6-113
Connecting Rod Bolt G u i d e Set Installed
3. F r o m beneath engine, pull connecting rod, with
bearing shell i n place, into position against crankpin.
4. Remove guide set J 5239. - Install bearing cap
and cap nuts and tighten to 43 l b . f t . torque.
5. Replace o i l pump and o i l baffle, i f they were
removed.
6. Install cylinder head and intake manifold.
CONNECTING
ROD AND
PISTON
ASSEMBLY-
RECONDITION
NOTE;
Use care at all times when handling and
servicing
connecting rods and pistons.
To prevent
- possible
damage to these units, do not clamp rod
or piston in vise since they may become
distorted.
350 J 6647
400 & 428 J 5684
.
F i g . 6 - 1 1 4
Instal ling Piston Assembly