(1) General. Procedures for repair will be the same for a great percentage of parts and
components. To avoid repetition of instructions, general procedures for repair are detailed in
paragraphs below. After repair, clean all parts thoroughly to prevent metal chips from repair
operations, or abrasives used in repair operations from entering working parts of the engine.
Avoid damage to casting while using
welding equipment. Refer to TM 9-237 for
Replace all castings that are cracked or do not conform to tolerances specified in App G.
Repair minor damage to machined surfaces with a fine file, emery cloth, or crocus cloth
dipped in cleaning solvent.
Replace all castings on which machined surfaces are burred or nicked to the point of
impairing subsequent assembly or operation.
Repair minor warpage of mounting flanges and gasket surfaces by working surfaces
across a sheet of emery cloth held tightly on a surface plate or a flat surface. Finish
similarly using crocus cloth.
Replace castings having flanges which are warped to the point of impairing assembly or
Repair damaged pipe or cap screw threads in tapped holes with a thread tap.
(3) Ball Bearings.
in castings must be
in good condition to prevent oil or water leakage.
Replace all galled, pitted, or damaged ball bearings and any that do not conform to
tolerances specified in App G.
See TM 9-214 for maintenance of bearings.
(a) Replace all bent or loose studs or studs showing evidence of stretching.
(b) Repair minor thread damage with a thread chaser.