13
Backlash between hook drive gear and lower shaft gear
The gears turn smoothly and rotary play of the hook should be 0.8 mm or less when the tip
of hook is within the width of the feed dog as shown below.
1. Remove the base.
2. Remove the needle, needle plate and bobbin holder.
3. Turn the handwheel toward you so that the tip of the
rotary hook is within the width of feed dog. Turn the
rotary hook and check the clearance .
4. If the backlash is too much or too little, loosen
the setscrews of lower shaft bushings (front/rear)
and adjust the backlash following the adjustment
procedure in step 5.
* Turn the lower shaft bushings (front and rear) in
the same direction simultaneously and evenly.
5. If the backlash is too much, turn the lower shaft
bushing in direction A.
If the backlash is too little, turn the lower shaft bushing
in direction B.
6. Tighten the setscrews.
* After adjusting the backlash, check the needle bar
hight and hook timing. Adjust, if necessary.
7. Attach the bobbin holder, needle plate, presser foot
and needle.
8. Attach the base.
Lower shaft bushing (front)
Setscrew
Play: 8 mm or less with hook tip
within feed dog width
Tip of hook
(A)
(B)
Setscrew
Lower shaft bushing of the front side
Lower shaft bushing on the rear side
Setscrew
Lower shaft bushing (rear)
