TM9-2815-202-34 CAUTION 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. d. Inspection (1) Dome and Skirt NOTE Indications of overheating or burned spots may be result of an obstruction in connecting  rod  oil  passage. (a) (b) (c) 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 groove. Check cylinder liner and block bore for excessive out of round, taper, or high spots which could cause  failure  of  piston  (see  Para 4-34). (2) Piston Pin CAUTION When using a piston pin, do not refinish highly polished and lapped surface of pin in any way. NOTE 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. 4-135