JUKI APW-895, Engineer'S Manual

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Trouble Cause (1) Cause (2) Check and corrective measures
10. Troubles and corrective measures
(1) Machine head
1. Thread breakage (needle thread) 1-1) Scratches on the needle Removal of scratches from the thread path
thread path (use of fine sandpaper or buff)
1-2) The needle thread overloaded 2-A) Excessive tension of the Reduce the tension.
thread tension disk (Refer to the description of the thread tension disk.)
2-B) Excessive tension of the Reduce the tension.
thread take-up spring (Refer to the description of the thread take-up spring.)
2-C) Excessive or deficient stroke Adjust the stroke.
of the thread take-up spring (Refer to the description of the thread take-up spring.)
1-3) Inappropriate clearance between Adjust the clearance to 0.2 to 0.3 mm.
the inner hook guide and inner (Refer to the description of opener adjustment.)
hook
1-4) Inadequate hook mounting 4-A) Interference between the Adjust the clearance between the needle and the blade
needle and the blade point point of the hook.(Refer to adjustment of the hook
of the hook nd needle.)
4-B) Inappropriate timing for the Adjust the timing between the needle and the blade
needle and hook point of the hook.(Refer to adjustment of the hook
and needle.)
4-C) Blunt blade point of the hook Sharpen the blade point of the hook.
1-5) Insufficient hook oil Add hook oil to the appropriate level.
(Refer to adjustment of hook oil.)
2. Thread breakage (bobbin thread) 2-1) The bobbin thread overloaded 1-A) Excessive tension of the Reduce the tension of the bobbin thread.
bobbin thread
1-B) Thread caught between the Remove thread chips.
bobbin and inner hook
1-C) Deformed bobbin resulting in Replace the bobbin with new one.
non-smooth movement