Do not use crocus cloth on bushing side of pin. Bushing side requires a polished finish.
(4) Use crocus cloth wet with fuel oil to remove any trace of fretting and/or corrosion on
connecting rod saddle to piston pin contact surface.
(1) Dome and Skirt
Indications of overheating or burned spots may be result of an obstruction in
connecting rod oil passage.
Examine piston skirt and dome
for score marks, cracks, damaged
ring groove lands, loss of tin
plating, or indications of
overheating. Replace any piston
severely scored or overheated.
Check tapered fire ring groove
width with piston groove gage
(18). Slide NO-GO wire (0.106
inch diameter) of tool completely
around fire ring groove. Replace
dome if wire is below flush at any
one area. The GO wire (0.100
inch diameter) should be flush or
protrude slightly from fire ring
Check cylinder liner and block
bore for excessive out of round,
taper, or high spots which could
cause failure of piston (see Para
(2) Piston Pin
When using a piston pin, do not refinish highly polished and lapped surface of pin in
New piston pin has diameter of 1.4996 to 1.5000 inches. Replace piston pin if worn to
diameter of 1.4980 inches or less.
Inspect piston pin for signs of fretting.