TM 55-1520-240-23-1
1-16
REPLACE SCREW-THREAD INSERT (AVIM)
(Continued)
1-16
NOTE
Procedure is same to replace any
screw-thread insert. Typical insert
shown.
For more information on screw-thread
inserts, refer to TM 43-0104.
1.
Cover openings in housing (1) in area of insert
(2). Use barrier material (E80) and tape (E388).
NOTE
Use drill press if possible.
2.
Install drill bit in drill or drill press. Use
5/16 inch drill for inserts MS51991-206 and
MS51991-206L. Use 29/64 inch drill for insert
MS51991-208.
3.
Measure and record thickness of replacement
lock ring (3).
NOTE
Interlock need not be drilled away to
full depth. Three-quarters depth is
enough.
4.
Cut away interlock area (4) between insert
(2) and lock ring (3) by drilling through center
of insert. Do not drill deeper than lock ring
thickness recorded in step 3. Use several light
cuts. Pull back drill between cuts to clear chips
and check depth.
NOTE
As insert comes out, it will lift out
remaining part of lock ring. If it
does not, use punch to collapse and
remove remaining part of ring.
5.
Turn and remove insert (2) and remaining part
of lock ring (3) from housing (1). Use screw
extractor.
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