13
990D
Correct Setting:
The upper knife timing is the same as that of the needle bar. In fact, when the needle bar is at
highest position, the upper knife should be also at its highest position.
To adjust:
1. Remove the feed base cover unit.
2. Loosen two setscrews A, and move the balance weight to left.
3. Loosen two setscrews B, and adjust the needle and upper knife timing is being delay.
# Turn the upper knife drive cam to the direction D when the upper knife timing is being delay.
# Turn the upper knife drive cam to the direciton E when the upper knife timing is too soon.
4. Tighten the two setscrews B firmly. Move the balance weight to right.
Match the guide line on the balance weight with the one of the main shaft correctly.
Thennn tighten the two screws A.
5. Turn the handwheel toward you one cycle, and recheck the needle and the upper knife timing.
6. Attach the feed base cover.
TO ADJUST THE TIMING OF THE NEEDLE AND THE UPPER KNIFE
