Chevrolet 70 1969 Series, Shop Manual

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E N G IN E 6-11
'
_______________________________TP 3869
Figure 15— M e a s u r in g B e a r in g Thickness
Figure 1 6 — C h e c k in g S q u a re n e ss at Clutch H o u s in g Rear Face w ith D ial
indicator
Figure 17— Using Indicator to Check Clutch Housing Pilot Hole Location
Figure 1 8 — C h e c k in g Pilot H ole C oncentricity a t F lyw h eel H o u s in g
C R A N K SH A F T A N D B E A R IN G S
C L E A N IN G
1. Clean oil passages with steam and blow dry with
compressed air. Prod oil passages if necessary to re­
move obstructions.
2. Use compressed air to thoroughly dry main bearing
journals, crankpins and other ground surfaces. Apply
light coat of oil to prevent rusting.
IN S P E C T IO N O F C R A N K S H A F T
Carefully inspect for checks or cracks in crankshaft.
Replace if cracks are evident. M agna-Flux inspection
method is recommended for detecting fractures in crank­
shafts.
A L IG N M E N T O F B E A R IN G JO U R N A L S
With crankshaft supported at front and rear journals,
check alignment at adjacent intermediate journals using
dial indicator. If run-out is in opposite directions, the sum
must not exceed 0.003 inch T.I.R. If run-out at adjacent
journals is in same direction, the difference must not ex­
ceed 0.003 inch T.I.R. If high spots (run-out) at adacent
journals are at right angles to each other, the sum must
not exceed 0.004 inch T.I.R. or 0.002 inch on each jo u r­
nal. If run-out is greater than shown in “ Specifications"
at end of this section, the crankshaft must be replaced or
straightened. Straightening must be done with great care
by experienced personnel.
B E A R IN G JO U R N A L S
Examine connecting rod and main bearing journals on
crankshaft for scoring or other imperfections. Slight
roughness can sometimes be removed or smoothed up
with a fine hone. Examine cheeks on crankshaft at rear
C H EV R O LE" SERIES 70-80 HEAVY DUTY TRUCK S H O P M A N U A l