Main journal location
Crankpin journal locations
A. No. 1
F. No. 1 cylinder
G. No. 2 cylinder
C. No. 3
No. 3 cylinder
D. No. 4
E. No. 5
7. Install the rod cap and torque the nuts to
17.5 ft.-lb. (2.4 mkg).
8. Remove the rod cap.
9. Measure the width of the flattened
instructions (Figure 33). The standard
connecting rod big-end bearing clearance is
0.00 12-0.0023 in. (0.03 1-0.059 mm). The
maximum service limit is 0.0039 in. (0.10
10. Compare both ends of the Plastigage
strip. A difference of 0.001 in. (0.025 mm) or
more indicates a tapered journal (which
should be reground) or a bent or twisted rod.
Confirm with micrometer measurement of
the journal OD.
11. If the clearance is larger than the service
limit, measure the OD of the crankpin journal
with a micrometer. The minimum crankpin
journal OD (service limit) is 1.298 in. (32.97
12. If the OD is smaller than the service
limit, the crankshaft should be replaced as
a. Check the connecting rod at the points
indicated in Figure 34 for the big end
bore diameter mark. The connecting rod
will be marked with an "0" or there will
be no mark.
a new crankshaft. Then
cross-reference the crankpin diameter
markings (Figure 35) with the upper
connecting rod marks (Figure 34). Refer
to Table 13 to select new connecting rod
13. If the O D is larger than the service limit,
install new bearing inserts colored green.
Always replace all 8 inserts at the same time.
14. Recheck the clearance with the new
inserts or crankshaft. The clearance should be
less than the service limit and as close to
standard as possible.
15. Repeat for each connecting rod.
16. Clean and oil the crankpin journals and
bearing insert faces.
17. Install the bearing inserts in each
connecting rod and cap. Make sure their
locking tabs are seated in the notches.
the old inserts are reused, be sure
they are installed in their original
positions for minimum wear.
18. Reassemble the engine as described in
this supplement and in Chapter Four of the
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