Pontiac tempest 1968 Service Manual page 286

V-8 E N G I N E
6-69
F i g . 6-123 Checking Ring G a p
5. Measure side clearance of rings in ring groove
(Fig. 6-124) as each ring is installed. Clearance with
new pistons and rings should be .0015 TT -.0050 ,T .
If side clearance is excessive, piston should be
replaced.
CRANKSHAFT-CHECK
These checks are to be made with oil pan and baffle
removed and with all main caps and rods installed
and properly torqued.
1, Check endplay (Fig. 6-125). Using hammer, tap
end of crankshaft at rear until it is tight against front
of thrust bearing (No. 4 main bearing). Measure
clearance between crankshaft counterweight and thrust
bearing. Proper clearance is .003" to .009". If
clearance is outside these limits, a new thrust bear­
ing is required.
2 . Check connecting
rod side clearance. Using
hammer, gently tap lower end of connecting rod
F i g . 6-125 Measuring Crankshaft End Play
toward front of engine. Measure clearance between
rear of connecting rod and crankpin. Proper clear­
ance is .006" to .011". If clearance is outside these
limits, a new rod or rods is required.
CRANKSHAFT-REMOVE AND REPLACE
In order to remove the crankshaft the engine as­
sembly must be removed from the vehicle.
The crankshaft can then be removed and replaced
with cylinder heads, pistons, rods, manifolds and
other upper engine components installed, but the fly­
wheel clutch and transmission assemblies must be
removed.
REMOVE
1. Remove engine and clutch (SM) as an assembly.
See E N G I N E - R E M O V E AND INSTALL.
2 . Remove clutch (SM) and install engine on suit­
able stand.
3. Remove spark plugs.
4. Remove engine oil pan.
5. Remove oil pump assembly and oil pump drive
shaft (Fig. 6-103).
6. Remove oil baffle and oil baffle tube.
7. Remove harmonic balancer.
8 . Remove fuel pump.
9. Remove timing chain cover, gasket and O-ring
seal.
F i g . 6-124 Measuring Side Clearance of Ring in Groove
10. Remove fuel pump eccentric and bushing (Fig.
6-95).