24
A
B
Lower shaft bushing
Hexagonal socket
screw (C)
Lower shaft gear
Hook driving gear
Lower shaft gear
Lower bushing of the front side
Lower bushing of the belt cover
Lower shaft bushing
Hexago-
nal socket
screw (D)
Mechanical adjustment
Backlash between hook drive gear and lower shaft gear
The rotary play of the hook should be 0.8 mm or less when the tip of rotary hook is within the width of feed dog.
Tip of rotary hook
1. Remove the base cover and bed cover (see page 2 and 3).
2. Remove the presser foot, the needle plate and the bobbin
holder. (see page 4)
* Cover the needle plate with the fabric to prevent
damaging the needle plate when removing.
3. Turn the handwheel toward you so the the tip of the rotary
hook is within the width of feed dog as shown in figure 1.
Check the rotary play of the hook.
4. If the backlash is too much or too little, loosen the hexagonal
socket screw (C) and (D) and following the adjustment
procedure.
If the backlash is too great (more than 0.8 mm), turn the
lower shaft bushings in direction A. If the engagement of
gear is too tight, and the machine does not turn smoothly, )
turn the lower shaft bushings in direction B.
Adjust the grooves of the lower shaft bushing as well.
5. Tighten the hexagonal socket screws.
Width of feed dog
groove
groove
