TM 5-4320-302-14
6-16.
PISTON ASSEMBLY (CONT)
Location/Item
Action
Remarks
12. Oil control ring groove
Measure axial ring clearance with standard clearance gage. Measurement should be
0.1980 to 0.1988 inch (5.03 to 5.05 mm). If measurement is greater than 0.1988 inch
(5.05 mm), replace piston.
WARNING
Dry cleaning solvent is flammable and potentially dangerous to people and property. Do not use near
open flame, sparks, excessive heat, or on hot surfaces. Flash point of P-D-680 solvent is 1000 to 138°F
(38° to 59°C). Use solvent in a well-ventilated area, and avoid inhaling fumes. If repeatedly exposed to
fumes, seek fresh air and immediate medical help. Avoid prolonged exposure of skin to solvent. Wash
exposed skin immediately and thoroughly.
Death or severe injury might result when compressed air is used to blow dirt from skin or clothing. Air
entering body openings is extremely dangerous. Compressed air used for cleaning shall not exceed 100
psi (690 kPa). Use goggles or face shield for eye protection. Do not direct airstream against skin.
13. Piston ring grooves
If any axial ring clearance measurements are smaller than the minimum values given
above, piston ring grooves may be clogged with carbon deposits. Reclean piston with P-
D-680 solvent and wire brush. Dry with compressed air. Take measurements again. If
still smaller than minimum values, piston is damaged or defective. Replace piston.
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