TM 5-3895-376-14&P
5-12. PISTON ASSEMBLY MAINTENANCE INSTRUCTIONS - Continued
CLEANING
WARNING
P-D-680, Type Ill, is moderately toxic to
the skin, eyes and respiratory tract;
avoid prolonged exposure. Skin and
eye protection is required. Good ventila-
tion is required. Do not use near open
flame or excessive heat. Flash point is
200 F (93.3 C).
1.
Clean the parts in dry cleaning solvent and dry
thoroughly.
2.
Ensure that any carbon deposits around top of
piston are removed.
INSPECTION
1.
Inspect outside surface of piston (2) walls for
scoring. Replace the piston if scored.
2.
Measure clearance between piston (2) and mid-
dle ring with a feeler gauge. Replace ring set if
clearance is greater than 0.0055 in. (0.14 mm).
3.
Measure clearance between piston (2) and oil
control ring with a feeler gauge. Replace ring set
if clearance is greater than 0.0055 in. (0.14 mm).
4.
Measure clearance between piston (2) and com-
pression ring with a feeler gauge. Replace ring
set if clearance is greater than 0.0063 in. (0.16
mm).
5.
Measure gap of compression and middle rings
with a feeler gauge. Replace ring set if gap clear-
ance is greater than 0.0433 in. (1.1 mm).
6.
Measure gap of oil control ring with a feeler
gauge. Replace ring set if gap clearance is
greater than 0.0394 in. (1.0 mm).
7.
Inspect the piston pin (4) for scoring. Replace pis-
ton pin if scored on outside diameter.
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