Frozen Stitch Length on Singer 144W103

[friquant]

How to get this stitch length mechanism freed up?

In this first photo of the main shaft, we have the timing cog on the right, the feed shaft cap in the middle, and the stitch length mechanism on the left. The large hole in the middle of the stitch length mechanism is for a set screw which I have removed. The smaller hole (upper right) of the stitch length mechanism is where I have removed the lock screw. so that the adjustment can actually be made.

Then I rotate the handwheel some, and now we see a different set screw (lower left, already loosened) and the big adjustment screw next to it.

The adjustment screw can move about 200 degrees from left to right before it binds. I've soaked the adjustment screw and the hole where the lock screw goes with marvel mystery oil, and even squirted some between the adjustment mechanism and the feed shaft cap. I've tapped on the adjustment screw with a hammer (using a metal screwdriver as a go-between). I've tapped the feed shaft with a hammer. Still nothing budging.

Is there anything else I should try (or shouldn't try) to get this to move?

 

[friquant]

Here is the relevant section of the manual.

I assume that turning the adjustment screw clockwise is meant to bring the ex-center closer to the center of the shaft.

[CowboyBob]

There's 2 ways to fix it,replace it OR try sewing & using it w/o locking it up should make the part rock in the grooves to get it to free up,you need to tighten the smaller screw since that is what connects the stitch cam to the shaft.

[kgg]

14 hours ago, friquant said:

Here is the relevant section of the manual.

I would get a wire brush and scrap all round the unit particularly around the feed eccentric seam and then add a few drops of good old fashion diesel around the feed eccentric seam. Wait about 24 hours to let it soak in, a few light tabs with a hammer and without any needle or bobbin run it at different speeds for a few minutes. If it hasn't freed up start over with a few more drops of diesel. Once freed oil the heck out of it with some synthetic transmission oil.

If you can't get it freed like @CowboyBob has suggest replace the unit. 

kgg

Edited 4 hours ago by kgg

[friquant]

3 hours ago, CowboyBob said:

try sewing & using it w/o locking it up should make the part rock in the grooves to get it to free up

That sounds good! I'll do that as soon as I get the set screws sorted...both set screws (both the one that goes in the main-shaft-groove and the one that does not) have one ear broken off. Planning to cut a groove in the top of each set screws to make them serviceable again and put them back in for now.

3 hours ago, kgg said:

add a few drops of good old fashion diesel around the feed eccentric seam. Wait about 24 hours to let it soak in, a few light tabs with a hammer and without any needle or bobbin run it at different speeds for a few minutes.

Tempting...we just got the machine back to smelling good again after its initial bath in P'Blaster. 👃 I guess we could relegate it to the porch for a few days..

 

[CowboyBob]

@friquant  The new stitch length cam I have in stock uses allen screws to the shaft.the others are still slotted.