Problem Cause Check Solut ion Page
Nee dle
breakage
Improper needle
installation
Needle facing, he ight Re install needle . 4
Bent needle
Blunt needle tip
jammed eye
Needle Replace needle 4
Improper feed timing _ Adjust feed timing. 16
Improper needle to
ro tary h ook timing
Needle bar stro ke
Adjust needle to rotary
hook timing.
15
Needle bar height
Adjust needle to rotary
hook timing.
15
Needle to ro tary
ho ok gap
Adjust needle to rotary
hook timing.
15
Thread wiper too high
Thread wiper
position
Adjust thread wiper
position with screw.
Thr ead
breakage
Improper threading Threading Rethread. 4
Bent needle
Blunt needle tip
jammed eye
Needle Replace needle 4
Improper needle
installation
Needle facing, he ight Re install needle . 4
Excessive needle
thread tension
Needle thread
te nsio n
Adjust needle thread
tension.
6
Excessive bobbin
thread tension
Bobbin thread
te nsio n
Adjust bobbin thread
tension.
6
Loose ne edle thread
Thread take-up
spring operation
Adjust thread take-up
spring.
6
Insufficient rotary hook
lubrication
Oil supply Adjust oil supply. 2
TROUBLESHOOTING GUIDE