P-D-680 SOLVENT IS POTENTIALLY DANGEROUS. AVOID PROLONGED OR
REPEATED CONTACT WITH SKIN. KEEP AWAY FROM FLAME OR EXCESSIVE
(3) Repair minor damage to machined surfaces with a fine file, emery cloth, or crocus cloth dipped in dry
cleaning solvent. Replace all castings on which machined surfaces are burred or nicked to the point of
impairing subsequent assembly or operation.
(4) Repair minor warpage of mounting flanges and gasket surfaces by working the surface across a sheet of
emery cloth held tightly on a surface plate or a similar flat surface. Finish similarly with crocus cloth.
Replace castings having flanges which are warped to the point of impairing assembly or operation.
(5) Repair damaged pipe or capscrew threads in tapped holes with a tap.
Pipe plug threads in castings must be in good condition to prevent oil or water
c. Ball Bearings.
(1) Replace all galled, pitted, or damaged ball bearings.
(2) Replace all ball bearings which do not conform to tolerances specified in repair standards (Table 3-1).
(3) Refer to TM 9-214 for maintenance of antifriction bearings.
d. Studs. Replace all bent or loose studs and studs showing evidence of stretching. Repair minor thread damage
with a thread chaser. Replace all studs having stripped or damaged threads. Remove and replace studs as
outlined in (1) and (2), below.
(1) Removal. Using a stud extractor, back the studs out slowly to avoid heating and possible seizure. When
the studs are broken off too short to use a stud extractor, drill the stud and extract it with an easy out.
Another method of removal is to use a welding torch and heat stud. Apply a wax stick to stud allowing
melted wax to flow into threads. While stud is still hot, use vise grips and carefully turn stud until it' comes
out. Take care not to break stud.
(2) Replacement. Only standard studs are supplied for replac ement. If threaded openings are damaged and
retapping will not clean up threads, drill and tap opening in casting and install a threaded insert.