To Time The Sewing Hook And Also Set The Sewing Hook Sidewise In Relation To The Needle - Singer 491D Service Manual

TO TIME THE SEWING HOOK AND ALSO SET THE
SEWING HOOK SIDEWISE IN RELATION TO THE NEEDLE
PREPARATION:
Remove presser foot, slide plate, throat
plate and feed dog.
CHECK:
When lower timing mark on needle bar is
level with lower end of lower needle bar
bushing A as shown in Fig. 7, the point of the
sewing hook should be at the center of the
needle, as shown in Fig. 7.
Also, when point of sewing hock passes
needle, clearance between hook point K,
Fig. 8 and needle should be approximately
equal to thickness of a piece of ordinary
notepaper (about .13 mm), as shown in Fig. 9.
NOTE: Not only point of sewing hook
but entire "FLAT" of hook point should clear
scarf on needle blade. Normally, a .5 mm
clearance is provided between hub of hook
and oil retaining collar.
SETTING:
Loosen two set screws L, Fig. 7 in hub
of hook. Then retighten one of the set
screws very lightly so that the sewing hook
can still be turned on the shaft.
Hold shaft immovable and turn hook as
required to bring point of hook to center
of needle as shown in Fig. 7 and at the same
time adjust clearance between needle and
hook point as shown in Fig. 9.
Tighten set screws L lightly, turn
machine pulley to make certain the sewing
hook is correctly set in relation to the
needle. Then securely tighter set screws L.
Fig. 9
- 5 -
A
LOWER
TIMING
MARK
HOOK POINT
AT CENTER
OF NEEDLE
L
FLAT OF
HOOK POINT
ON UPWARD
STROKE
Fig. 7
K
HOOK
POINT
Fig. 8
NOTEPAPER