TM 5-4320-302-14
6-17. CONNECTING ROD ASSEMBLY (CONT)
Location/Item
Action
Remarks
14. Big-end
a.
Measure with inside micrometer at points 1
bearing bore
and 2 and along axis A and B. Measurement
should be 2.0488 to 2.0501 inches (52.04 to
52.073 mm) for nominal bearing bore but
respectively smaller for undersized bores.
NOTE
See chart for nominal and undersized bore sizes for big-end bearing.
b.
If any measurement is outside the tolerance
limits, replace the big-end bearing. Make sure
that measurements at points 1 and 2 are not
different
nor
outside
the
tolerance
limits
indicating that bearing is wearing in a conical
shape. Make sure measurements along axis A
and B are not different nor outside the tolerance
limits indicating the bearing is wearing in an
oval shape. If bearing is wearing out-of-round,
replace it and check the crankpin on the
crankshaft. Follow procedure described in
paragraph 6-18. Also check pistons and
cylinders for unusual wear. Follow procedures
described in paragraphs 6-15 and 6-16.
6-131
