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To adjust the upper thread tension release (2)
Approximately 0.8 mm
Upper thread tension disks should open 0.8 mm when the tension thread release motor
operates. If not, adjust follows.
1. Remove the face plate, top cover and thread guide
cover (refer to pages 1 and 5).
2. Set the thread tension dial at “9” and lower the presser
foot lifter.
3. Turn the thread tension release gear counterclockwise
until it stops. (Fig. 1)
4. Check the clearance of upper thread tension disks.
The clearance should be approximatery 0.8 mm.
If the clearance is smaller than 0.8 mm:
Loosen the setscrews A and B. Tighten the setscrew
B lightly. Remove setscrew C and slide the base to the
front. Tighten the setscrew A and B securely. Tighten the
setscrew C.
If the clearance is larger than 0.8 mm:
Loosen the setscrews A and B. Tighten the setscrew
B lightly. Remove setscrew C and slide the base to the
rear. Tighten the setscrew A and B securely. Tighten the
setscrew C.
NOTE:
Turn the setscrew B with the plate positioned in the front
cover or the top cover can be damaged.
Set the plate inside the front cover, not to damage the top
cover.
5. Attach the thread guide cover, face plate and top
cover.
To check:
Make sure that the thread tension release plate has
a play when turning the thread tension release gear
counterclockwise until it stops.
Thread tension release gear
(Fig. 1)
Setscrew A
Setscrew B
Thread tension release plate
Base
Front
Setscrew C
Plate
