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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
5-2) Looper does not scoop
the middle needle thread.
2-A) Looper
A-1) Incorrect shape of pointed end of loop-
er disables scooping a loop.
Replace it with the genuine part.
2-B) Needle
B-1) Needle bend, incorrect needle mount-
ing direction, wrong needle
Replace the needle with new one. Cor-
rect the mounting direction.
Use UY128GAS.
2-C) Auxiliary thread tension
C-1) Being used.
Do not use.
2-D) Needle thread guide rod
D-1) Height is too low.
Correct the height to appropriate height.
2-E) Needle height
E-1) Needle bar height is too low.
Refer to the standard adjustment figures.
2-F) Threading
F-1) Incorrect threading
Refer to threading diagram.
2-G) Needle thread guard
G-1) Being used.
Do not use.
2-H) Spreader
H-1) Spreader thread tension is too strong.
Reduce the tension.
2-I)
Needle heat
I-1) Stitch skip occurs before thread break-
age produced by needle heat.
Same described in page "Thread break-
age by needle heat"
2-J) Looper adjustment
J-1) Incorrect clearance adjustment, incor-
rect returning amount adjustment
Refer to standard adjustment.
2-K) Needle guard, front and
rear
K-1) Incorrect contact amount, incorrect
height
Refer to the standard adjustment figures.
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