ARMY TM 9-6115-670-14&P
6-50
6.22. PISTONS.
This task covers: a. Test
b. Replace
INITIAL SETUP
Tools
General Mechanic's Tool Kit
(Item 1, Appendix B)
Inside Micrometer Caliper
(Item 42, Appendix B)
Piston Ring Compressor
(Item 41, Appendix B)
Equipment Conditions
Oil pan strainer removed (para 5.9.).
Cylinder head removed (para 6.5.).
Materials/Parts
Lubricating Oil
(Items 10-13, Appendix F)
Piston
TEST
a. Remove piston from cylinder (perform steps a - d of REPLACE).
b. Remove connecting rod from piston (perform steps a - b of REPLACE, para 6.23.).
c. Use inside micrometer caliper to measure the ID of the piston pinbore in both the horizontal and
vertical positions. It should measure between 0.78740 and 0.78791 in. (20.000 and 20.013
mm).
d. If piston pinbore exceeds 0.7894 in. (20.05 mm), replace piston.
CAUTIONS
Install piston ONLY into the same cylinder it was
removed from.
Pistons are not symmetrical. Make sure piston
is aligned in cylinder properly.
