TM 9-2815-237-34 c. Bearings. CAUTION All   engine   connecting   rod   and   main   bearings   will   be   replaced   if   one o r    m o r e    b e a r i n g s    f a i l . Check   all   bearings   for   conformance   to   applicable   repair   standards. d. Bushings and Bushing-Type Bearings. (1) Check  all  bushings  and  bushing-type  bearings  for  secure  fit,  evidence  of  heating,  wear,  burrs, nicks,   and   out-of-round   conditions. from e. f. g. h. i. j. (2) Check for dirt in lubrication holes or grooves. Holes and grooves must be clean and free damage. Machined  Parts. (1) Check machined parts for cracks, distortion, and damage. (2) Check all surfaces for nicks, burrs, and raised metal. Studs,  Bolts,  and  Capscrews.  Replace if bent, loose, stretched, or threads are damaged. Gears. NOTE When gear teeth wear limits are not established, good judgment is required  to  determine  if  gear  replacement  is  necessary. (1) Inspect all gears for cracks and missing teeth. Replace if cracked or teeth are missing. (2) Inspect gear teeth for wear, sharp fins, burrs, and galled or pitted surfaces. (3) Inspect splines for wear, burrs, and galled or pitted surfaces. (4) Check keyway slots for wear and/or damage. Oil Seals. Oil seals are mandatory replacement items. Casting Plugs. Inspect for leakage. Replace plugs when leakage is present. Springs.  Inspect for damaged, distorted, and collapsed coils. Snaprings, Retaining Rings, and Washers. Many of these parts are mandatory replacement k. items.  Inspect  all  others  for  obvious  damage. 2-11.   REPAIR a. General Instructions.  Repair of most parts and components is limited to general procedures outlined in applicable maintenance instructions and the following detailed procedures “b” through “h”. CAUTION Repaired items must be thoroughly cleaned to remove metal chips and abrasives to prevent them from entering working parts of the  engine. b.  Castings. (1) All cracked castings will be replaced. (2) Only minor repairs to machined surfaces, flanges, and gasket mating surfaces are permitted. Remove  minor  nicks,  burrs,  and/or  scratches  with: (a) Fine  mill  file. (b) Abrasive  crocus  cloth  dipped  in  cleaning  solvent. (c) Lapping  across  a  surface  plate. (d) Remachining of machined surfaces to repair damage, warpage, or uneven surfaces is not permitted.   Replace   castings. (3) Repair damaged threaded pipe plug and/or capscrew holes with a thread tap or repair oversize holes  with  threaded  inserts. 2-5