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1-11) Defective feed timing
11-A) Feed timing is earlier than the standard one.
Re-adjust the feed timing. (Refer to [3-(6)]).
11-B)Height of the feed dog differs from the
Re-adjust the height of the feed dog. (Refer to [3-
standard value.
(6)-4)])
1-12) Defective hook timing
12-A) Hook timing is too early.
Retard the hook timing.
1-13)Defective needle entry
Adjust so that the needle enters just at the center
of the needle slot in the feed dog.
1-14)Inner hook opening lever is defective.
14-A) Clearance between the hook and the
Decrease the clearance.
inner hook opening is too large.
1-15) Heavy threads used
Replace it with the feed dog (40062827) for thick threads.
Remove the pre-tension part of the needle thread
clamp device unit.
Increase the needle size number. (Replace the
needle with a thicker one.)
2. Stitch Skipping
2-1) Defective needle
1-A) Bent needle
Replace the needle with a new one.
Stitches are not finishing
completion since sewing
1-B) The needle is installed facing in the
Re-install the needle in the correct manner.
threads are not made into
wrong direction.
stitches in part.
1-C) Tip of the needle is blunt.
Replace the needle with a new one.
1-D) The needle is too thick or too thin for the
Replace the needle with a new one.
thread used.
2-2) Defective hook components
2-A) Blade point of the hook is blunt or worn out.
Correct the blade point of the hook or replace
the hook with a new one.
2-B) Incorrect hook timing
Re-adjust the hook timing.
2-C) Height of the needle bar is not correct.
Re-adjust the vertical position of the needle bar in
the light of the blade point of the hook.
2-D) Clearance between the blade point of
Minimize the clearance.
the hook and the needle is not correct.
2-E) Effective amount of the needle guard is wrong.
Adjust the effective amount of the needle guard.
2-F) Thread loops are not made with consistency.
Wind the thread around the needle.
2-3) The needle thread tension is too high.
Decrease the needle tension.
2-4) Sewing speed is too high.
Decrease the sewing speed.
Trouble
Cause (1)
Cause (2)
Check Procedure and Corrective Measures
Continued from the previous page
Stitch Skipping
Needle
Thread
Bobbin
Thread
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