TM 5-4320-302-14
6-20. CRANKSHAFT ASSEMBLY (CONT)
Location/Item
Action
Remarks
33. Main bearing
If main bearing bracket bore is within or just
support bore
slightly outside tolerance limits or if a new
main bearing bracket is being used, loosen
screws alternately and evenly far enough to be
able to install main bearing supports and pin.
Make sure matchmarks are correctly alined if
new supports are not being installed. Make sure
support with oil passage is installed in upper
main bearing bracket. If new brackets or sup-
ports are being installed, matchmark them.
Tighten and retighten screws as in step 32.
Measure main bearing support bore with precision
micrometer at points 1 and 2 and along axis A and
B as in step 32. Measurements for a normal size
main bearing support should be 2.3638 to 2.3655
inches (60.040 to 60.083 mm). If any measurement
is not within these tolerance limits, replace main
bearing support.
6-179