JUKI MOL-254 Engineer's Manual page 29

Adjustment Procedures
Loosen adjustment screw
and adjust the position of thread trimming solenoid arm so
that a clearance of 1 mm is provided between the cam face
of thread trimmer cam and the roller attaching face of cam
follower. Then, fix adjustment screw
in the thread trimming solenoid
.
22
− −
Results of Improper Adjustment
○ Thread trimming roller enters the
groove in thread trimmer cam
and failure of thread trimming or
machine-lock will occur.
○ Return to the initial position of the
thread trimmer mechanism is
delayed, or release of thread
tension disk rising is delayed. As
a result, defective thread
tightness at the start of sewing
or stitch skipping will occur.