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WARNING :
Turn OFF the power before starting the work so as to prevent accidents caused by abrupt start of the sewing machine
Trouble (1)
Trouble (2)
Cause (1)
Cause (2)
Check and corrective measures
From the previous page
5-4) Needle does not scoop
the looper thread. (Tri-
angle stitch skip) Middle
needle • Left needle
4-A) Looper
A-1) Ventral shape is incorrect.
Replace it with the genuine part.
4-B) Needle
B-1) Needle bend
Replace the needle with the new one.
4-C) Needle height
C-1) Needle bar position is too high.
Refer to the standard adjustment figures.
4-D) Threading
D-1) Incorrect threading
Refer to threading diagram.
4-E) Looper adjustment
E-1) Incorrect clearance adjustment, incor-
rect returning amount
Refer to the standard adjustment figures.
4-F) Looper thread tension
F-1) Tension is too weak.
Increase tension.
4-G) Looper thread cam tim-
ing
G-1) Looper thread cam timing is too early.
Refer to the standard adjustment figures.
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