Needle Position And Cam Follower Mechanism - Singer 250 Series Service Manual

II
Needle Position and Cam
Removal:
1) Remove
D
and
0 .
Follower Mechanism
252 2) Set stitch width lever on "Straight Stitch".
3) Remove screw
A.
4) Remove cam disengaging lever
B.
5) Remove spring C.
6) Remove follower D.
7) Remove tension spring E.
252-257 8) Loosen set screw f .
9) Remove stud G.
10) Move stitch width lever to the right "Max. width" .
11) Remove regulator block support H with eccentric screw I, lock nut L. slide J and
hinge
K.
257
12) Remove retaining ring M and washer.
252 13) Remove screw N and spring washer 0.
252-257 14) Remove cam follower hinge pin P.
15) Remove stitch pattern selector lever assembly 0.
16) Remove needle position lever assembly
R
(see caution below) .
Caution:
252-257 When removing needle position lever assembly R. be careful not to loose positioning pin
V and the spring X, as the pin V will pop out by decompression of spring X - See fig . XI.
Caution on reassembly:
a) Make certain spring X and positioning pin V have been inserted and that pin V does
not pop out while assembling needle position lever assembly U.
b) When inserting positioning pin V make certain it is inserted with the rounded end up.
252 c) When assembling lever 0. screw N and spring washer 0, make certain the spring
washer O is placed with concave lace downward .
252-257 d) Before assembling regulator block support H, make certain that the eccentric portion
of eccentric screw I is turned to the rear.
Adjustments:
Note: Before performing the adjustments of this group. check the adjustment on sideways setting
of needle bar and the stitch width lever stops as described in
IE.I.
Lateral adjustment of needle position:
1) Turn handwheel until the cam follower is on a crest of zig-zag cam pattern.
2) Move needle position lever Y to left.
3) Moving zig-zag bight amplitude lever to and fro there must not be any movement ol
needle bar.
4) II there is movement of needle bar, loosen the nut L and turn the eccentric screw I
to right or left until the movement disappears completely.
5) Tighten the nut
l
while holding the eccentric screw I.
6) Check center position of needle in throat plate and readjust. if necessary.
Caution:
Do not turn eccentric screw I more than a '/, turn either way to maintain eccentricity
towards the rear.
Adjustment of needle position lever to graphics on control panel:
Check:
1)
Assembte D .
252-257 2) Set needle posit ion lever S on " Center Needle Position ".
3) The marking line on lever knob Y should be right under the symbol for center needle
position on the control panel as shown in fig . X 2.
Setting:
1)
Ae move D .
252-257 2) Loosen screw Z.
3) Move lever knob Y as required and tighten screw Z.
FOAM 723 (1172)
29