JUKI MOL-254 Engineer's Manual page 53

Adjustment Procedures
1) Remove the cover from the hook base.
2) Loosen three setscrews
and adjust the hook timing.
(Caution) The timing has been factory-adjusted at the
time of delivery. Basically, do not loosen
setscrews
There is a marking.
in the removing shaft crank
.
46
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Results of Improper Adjustment
If the hook timing is not correct, the
needle will not enter the recess on
the shuttle body when it comes
down, causing the needle to
interfere with the hook. In this case,
needle breakage will occur or the
thread will fail to smoothly come out
of the hook. Or, the thread may fail
to come out of the hook resulting in
stitch skipping or thread breakage.
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