(burned), flaking, abrasion or scoring. If the
inserts are good, they may be reused if
clearance is satisfactory. If any insert is
questionable, replace the entire set.
4. Wipe any oil from the crankshaft main
journals and the inserts.
5. Set the upper crankcase upside down on
the workbench. Place it on wood blocks to
prevent damage to the cylinder studs.
6. Install the main bearing inserts in the
upper (Figure 30) and lower (Figure 31)
crankcase halves. Make sure their locking
tabs are seated in the notches.
the old inserts are reused, be sure
they are installed in their original
positions to prevent rapid wear.
7. Install the crankshaft in the upper
8. Place a strip of Plastigage over each main
bearing journal parallel to the crankshaft.
Do not put Plastigage over the oil holes.
Do not rotate the crankshaft while the
Plastigage strips are in place.
9. Carefully turn the lower crankcase over
and install it on the upper crankcase.
10. Apply oil to the bolt threads and loosely
install the 10 large crankcase bolts (Figure
11: Torque the 10 large bolts in 2 stages to 18
ft.-lb. (2.5 mkg). Follow the sequence
numbers cast into the bottom of the engine
next to the bolts.
12. Remove the bolts in the same sequence
you tightened them and remove the lower
13. Measure the width of the flattened
instructions (Figure 33). The standard
0.0005-0.0014 in. (0.014-0.038 mm). The
maximum service limit is 0.0031 in. (0.08
14. Compare both ends of the Plastigage
strip. A difference of 0.001 in. (0.025 mm) or
more indicates a tapered journal which
micrometer measurement of the journal OD.
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