To Remove And Replace The Needle Bar - Singer 491D Service Manual

3. Turn shaft so that one of the two set screws K2 will bear upon the upper
gear flat on the shaft and tighten the set screws K2.
4. Replace and set hook shaft bevel gear as instructed in Step 5 on page 10.
5. Replace oil pump, as instructed on page 11.
6. Replace top cover.
TO REMOVE AND REPLACE THE NEEDLE BAR (See Fig. 20)
Q2
R2
J
H
Fig. 20
Remove the needle bar in the following
manner:-
M2
1. Remove needle, needle set screw and
needle bar thread guard.
2. Remove face plate.
3. Loosen clamping screw C.
4. Loosen screw M2 sufficiently to allow
P2
needle bar to pass, then slip needle bar
up through both needle bar bushings and
out of machine.
N2
NOTE: If it becomes necessary to remove
upper needle bar bushing N2, first remove screw
M2 and take-up lever oil guard P2. Then loosen
set screw Q2 and drive bushing N2 down and out
of head of machine. Use a 10 mm driving pin.
Before replacing needle bar, replace upper
needle bar bushing N2, by driving it down into
C
hole provided for it in head of the machine.
Make certain top of bushing N2 is level with
top of arm. Tighten set screw Q2.
Replace the needle bar in the following
manner:-
1. Slip needle bar down through both bushings
in head of the machine. Tighten screw C.
2. Replace needle bar thread guard, needle
set screw and needle.
3. Set needle bar at correct height and re-
place face plate as instructed in page 2.
4. Replace oil guard P2 and fasten it secure-
ly to bushing with set screw M2.
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