Baby Lock EmbroideryPro_BMP8_InstructionRef (BMP8) Instruction and Reference Guide - Manual (Page 221)

APPENDIX —————————————————————————————————————————————————————
204
The upper thread
breaks.
Sliding surface on hook is not
smooth. There are burns on it.
1 Hook race area
Consult your nearest authorized
retailer.
The thread is loose in the hook
area.
Remove the loose thread. If the
thread is tangled in the hook,
clean the hook.
p.195
The play between the hook and
the race is too much.
Consult your nearest authorized
retailer.
The hook does not rotate
smoothly.
Remove lint, and clean and
apply oil.
p.195, 198
The space between the hook
stopper and the hook cannot be
adjusted.
Consult your nearest authorized
retailer.
The upper thread is not threaded
correctly.
Pull the upper thread by hand
from below the presser foot, and
check that the thread moves
smoothly. If the thread does not
move smoothly, it is not
correctly threaded.
Un-thread the machine and
re-thread the machine.
Make sure the thread is correctly
positioned in the needle bar
thread guide.
p.35-38
Upper thread is not positioned
in upper or middle thread guide.
Make sure thread passes
completely under upper and
middle thread guide.
p.36-37
There are knots or tangles in the
thread.
Remove any knots or tangles.
The upper thread tension is too
high.
Decrease the upper thread
tension.
p.86
The lower thread tension is
incorrect.
The thread does not roll out of
the bobbin case smoothly.
Adjust the lower thread tension. p.85
The bobbin case is damaged.
Replace the bobbin case with a
new one.
p.15
The bobbin thread is not wound
correctly.
Check that the bobbin is wound
so that it about 80% full and that
the thread is evenly wound. If
the bobbin is not correctly
wound, replace the bobbin with
one that is correctly wound or
rewind the bobbin.
p.15
A bobbin designed specifically
for this machine is not used.
Use the correct bobbin. p.15
Symptom Probable Cause Remedy Reference Page
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