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Troubleshooting Chart—Continued | Up
Aircrew Survival Equipmentman 1 & C - Aviation theories and other practices | Next
TIMING AND ADJUSTMENTS |
Table 4-4.—Troubleshooting Chart-Continued
3. Miscellaneous Problems—Continued
Trouble
Probable Cause
Remedy
N O T
Indicating disc loose
Reset and tighten.
S T I T C H I NG
AS
Indicating disc incorrectly set
Reset and tighten.
I N D I C A T ED
Automatically changing stitches
Adjust feed eccentric gib.
S L U G G I SH
Improper oil or accumulation of
Clean with recommended solvent and
foreign matter
lubricant.
.
BINDS
Bobbin-case opener set too close
Arm shaft friction washer missing
Balance wheel improperly set for
tolerance
Needlebar too high or too low
Feed-driving connection against
eccentric body
Hook guard washer rubbing bob-
bin-case opener lever link
Pinion gear against saddle
Hook driving gear against saddle
Bobbin-case thread jam
Feed dogs against throat plate
Feed bar hinge stud screw
Wrong bed slide over sewing hook
Alternating pressers out of adjust-
ment
Set to allow thread passage around bob-
bin-case lug.
Install friction washer.
Tighten adjusting screw, back off one-
quarter turn, tap with mallet.
Reset in frame.
Set connection flush with cam.
Replace washer. Adjust hook assembly for
tolerance.
Relocate on hook shaft.
Relocate to center on center line of
sewing hook shaft.
Remove case, clear, and reinstall.
Adjust to proper height. Adjust to center
of throat plate.
Adjust for proper operating tolerance.
Put recessed slide over sewing hook.
Reset.
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