Singer 111W155

[Dan_IN_MN]

I have my late dad's Singer 111W155 commercial sewing machine. He purchased it new in the early 50's. It's sown a lot. 

One day it wouldn't stitch. Needle wouldn't go through the hole in the feed dog. In fact the needle bar and feed dog don't move together. Broke the needle. I'm the only one who uses the machine. I've looked the machine over for something loose or broken and didn't find anything. The timing belt is in time and in good condition. 

The military manual hasn't been much help. Some of the pictures are messed up.

I made a short video attempting to show what happening. 

Thank you for your thoughts!

 

Dan_In_MN

Link to video. 

https://youtu.be/tBfok3Zu-Vk?si=d66XIaR5rbtZs0Af

[Wyowally]

I also have the same machine, redone by me with help from others on this forum. I am not near it and won't be for a while. My first thought is the main pinch screw (the big-headed one) in the exposed linkage on the back let slip. Not common, but it does squeeze a clamp, so unwanted rotation is possible. Next thought is lubrication dried out if it has sat for years. Another possibility is something moved in the internal feed eccentric that also adjusts the two feet and their movement and relationships. I did find the military manual I have pretty useful. On YT, search for Uwe Grosse and his videos - not all specific to Singers, but also the other machines of nearly identical design. I found this very good.