JUKI LU-2810 Series, Engineer'S Manual

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WARNING :
Turn �FF the power before starting the work so as to prevent accidents caused by abrupt start of the sewing machine.
Trouble Cause Checking Corrective measures
1. Thread breakage 1-1) Thread path, needle point,
hook blade point or in-
nerhook resting groove on
the throat plate has sharp
edges or burrs.
1-A) Check the sharp edge or burr
on the respective parts.
Remove the sharp edges or burrs on the blade
point of hook using a fine emery paper.
Buff up the groove section on the throat plate.
Replace the needle with a new one.
2. Thread is worn out. 2-1) Needle thread tension is too
high.
Adjust the needle thread tension.
2-2) Needle comes in contact
with the blade point of hook.
2-A) Check the clearance. Refer to “2.-(6) Needle-to-hook timing”.
2-3) Clearance of inner hook
guide is too large.
3-A) Check the clearance. Decrease the clearance.
Refer to “2.-(5) Adjusting the inner hook guide”.
2-4) Amount of oil in the hook is
insufficient.
4-A) Check the amount of oil in
the hook.
Adjust the amount of oil in the hook.
Refer to “2.-(16) Lubrication”.
2-5) Trimmed with the tooth of
the feed dog.
5-A) Check the feed dog. Provide a groove behind the feed dog needle
hole.
5-B) Check the alternate vertical
movement.
Reduce the amount of alternate vertical move-
ment.
5-C) Check the sewing speed. Reduce the sewing speed.
9. Troubles and corrective measures
(1) With regard to sewing
海外講習会用121122 LU-2810(-7)̲EM