5. TROUBLESHOOTING
120
Cause
Check
Remedy
Page
Upper thread
scissors
Upper thread scissors
operation
Adjust the upper thread scissors to the standard
setting.
89
Work clamp home
position sensor
Work clamp home
position sensor position
Adjust the work clamp home position sensor
position.
82
5-25. Lower thread is not trimmed (pulls when material is removed)
Cause
Check
Remedy
Page
Machine stopping
position
Rotary hook touches
lower thread retainer at
the stop position
Adjust the needle up stop position.
103
Fixed knife and movable
knife do not mesh.
Adjust the fixed knife set installation position.
96
Fixed knife set
Knife tip is bent or
chipped.
Repair or replace the knife.
-
5-26. Feed mechanism does not operate or motor is out of step
Cause
Check
Remedy
Page
Feed pulse motor
Cord connection
Check the cord connections and contacts.
-
Upper thread scissors
position
Remove and re-install the upper thread scissors.
91
Upper thread
scissors
Check if the cam opens
the stop plate.
Adjust the cam position.
* If the feed mechanism operates when the cam has
not opened the stop plate, the cutter will bump
against the upper thread scissors.
95
4021Q
Retainer
Inner rotary
hook presser
4024Q
Fixed knife
Movable knife
4025Q
Projection on scissors M is inserted.
* Always make sure that the upper
thread scissors are in the correct
position before use.
4018Q