Upper thread breaks
• Upper thread is not threaded correctly
o Correctly thread the machine
• Upper thread tension is to tight
o Reduce upper thread tension
• Needle is not installed correctly
o Install needle correctly
• Needle is bent or worn
o Replace the needle
• Presser foot height is incorrect
o Adjust presser foot height to thickness of material
• Presser foot has nicks or burrs on it
o Replace presser foot
• Needle is hitting the needle plate
o Reposition needle plate
• Presser foot is not correctly positioned to the needle plate
o Align presser foot to hole in the needle plate
• Rotary hook is dirty or needs to be oiled
o Clean and oil rotary hook
• Rotary hook over oiled
o Clean excess oil from rotary hook
• Needle bar(s) over oiled
o Clean excess oil from needle bar(s)
• Bobbin thread is not wound correctly
o Replace bobbin
• Bobbin case is damaged
o Change bobbin case
• Scratches on the sliding surface of the rotary hook
o Smooth scratches or replace rotary hook
• Poor quality thread
o Replace thread
• Fabric is not taut in the hoop
o Re-hoop garment
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For Technical Assistance Please Call Toll Free 1-877-4BROTHER