60
31. Sewing hook timing
Requirement:
When the needle bar has moved 2.2 mm upwards from its lowest position, with the machine set for
straight stitch and center needle position, the sewing hook point must be exactly behind the center line of
the needle (fig. 62).
Check:
z Remove presser foot and needle plate.
z Press the straight stitch button.
z Bring the needle bar to its lowest position by turning the handwheel.
z Push the spacer (63-102 600-18) onto the top of the needle bar and slide it upwards against the need
le bar frame (fig. 63).
z Push the needle-rise clamp (00-870 137-01) on the needle bar and tighten it lightly.
z Push the 2.2 mm feeler gauge (00-870 136-01) with its cutout on the needle bar above the needle-rise
clamp.
z Loosen the needle-rise clamp and push the 2.2 mm feeler gauge upwards against the spacer.
z Tighten the knurled screw on the needle-rise clamp.
z Slightly turn the handwheel back and forth.
z If there is any play on the feeler gauge, repeat this procedure.
z Remove the 2.2 mm feeler gauge.
z Turn the handwheel in sewing direction until the needle-rise clamp rests on the spacer.
This means that the needle has moved upwards by 2.2 mm to the needle rise position.
The hook point must now be exactly behind the center line of the needle (fig. 62).
Adjustment:
z If the setting is not correct, remove the needle-rise clamp.
z Loosen the two screws 108 (fig. 64).
z Refit the needle-rise clamp and repeat the operation as described under "Check", until the needle bar
has moved 2.2 mm upwards and the needle-rise clamp rests on the spacer.
z Turn the hook until the hook point is exactly behind the center line of the needle.
z Press sewing hook 107 and bevel gear 111 together so that there is no play between them, and tighten
one of screws 108.
Cross-check:
z Slightly turn the handwheel back and forth until the needle-rise clamp rests on the spacer (fig. 62).
The hook point must be exactly behind the center line of the needle.
z Remove the needle-rise clamp.
z Check that the hook shaft has no axial play.
z Tighten the two screws 108 very firmly.
