5-20. PISTON REPAIR/RING SET REPLACEMENT.
This task covers:
Shop Equipment, Machine Shop, Field
TM or Para
Maintenance, Basic, Less Power
Ring set, piston
a.Removal. Remove compression rings (1 and 2), and
oil ring (3) using a piston ring expander.
Measure new ring end gap (3 rings) by
placing ring to be checked in cylinder and
approximately one inch.
Remove piston and measure gap between
ring ends using calipers. Gaps should be
Two compression rings 0.011 to
0.019 in. (0.3 to 0.5 mm).
Oil control ring 0.009 to 0.019 in.
(0.25 to 0.5 mm).
If gap is too small, file ring ends to
achieve desired gap.