TM 5-3805-248-23-2
PISTON AND CONNECTING ROD MAINTENANCE - CONTINUED
0348 00
INSPECTION - CONTINUED
NOTE
Reference diameter for new piston is 2.0006+0.0003 (50.8152+0.0076 mm); reference diameter for new
pin is 1.998 + 0.0002 (50.7492+0.00508 mm). Maximum distance between pin bearing and worn pin is
0.003 in. (0.0762 mm). Replace piston if dimension is not correct. If correct, proceed to step 8.
Piston is reusable if there is clearance between flat edge of gage and piston, for both grooves. Replace
piston if flat edge of gage contacts piston at any of the four test points in either groove.
8.
Use keystone piston ring groove gage and piston ring
KEYSTONE PISTON
(7) to measure top two ring grooves of piston (4). Put
RING GROOVE GAGE
pin end of gage in piston groove at four places. Check
both grooves.
7
9.
Inspect top and second ring grooves of piston (4) for
burrs and closed oil holes. Remove burrs and clean oil
holes, if necessary.
4
SECOND
TOP
GROOVE
GROOVE
394-1165
0348 00-7