– 168 –
Trouble
Cause (1)
Cause (2)
Check and corrective measures
From the previous page
3-3) The stroke of the thread take-
up lever is too long.
Move the arm thread guide rightward to reduce
the thread feeding with the thread take-up
lever.
3-4) The stroke of the thread take-
up lever is too long.
Move the arm thread guide rightward to reduce
the thread feeding with the thread take-up
lever.
3-5) The matters related to the
hook are inappropriate.
5-A) The timing of the hook is too
early.
Set the timing of the hook to the standard or
slightly late level for cotton or spun thread.
5-B) The timing of the hook is too
late.
Set the timing of the hook to the slightly early
level for filament thread.
5-C) The clearance between the
hook and inner hook presser is
too small.
Increase the clearance to smooth the thread
passing.
5-D)
Hook oil is insufficient.
Adjust the oil volume to the appropriate level.
5-E) The hook is defective. (Thread
catch)
Replace the hook.
3-6) The thread path is defective.
6-A) The thread path is not smooth.
Finish the thread path appropriately.
6-B)
The thread path has a flaw.
Finish the thread path appropriately.
6-C) The thread path has an obsta-
cle.
Finish the thread path appropriately to correct
threading.
3-7) The bobbin or bobbin case is
defective.
7-A) Inappropriate engagement
between the bobbin and bobbin
case causes the bobbin thread
to be caught.
Replace the bobbin or bobbin case.
7-B) Thread has not properly been
wound around the bobbin.
The winding tension was too high or low.
7-C) The tension adjusting spring of
the bobbin case is defective.
Replace the bobbin case.
To the next page
To the next page