Originally Posted by
miriam
I spent some time trying to figure out a machine... It is a Singer 401. The motor spins like crazy when you turn the clutch to bobbin winder mode. If you try to sew it starts out going great then gets slower and slower and s l o w e r.... The machine turns fine. We tired a different motor and a couple different foot controllers. Turn it back to bobbin and away she goes... It seems to be the machine. It is VERY well oiled.
Release the clutch to wind a bobbin (without the BW contacting the wheel), and put some drag on the handwheel with your hand. See if the motor chugs down like it did before, but only from the load from your hand. If it does, I’d look further into the motor and controller. If not, I’d look further into the machine.
I had a 401A that was locked up and wouldn’t move at all. Wiggle-jiggles finally led me to believe it was in the upper shaft, but I couldn’t find anything. I finally decided that it must be just a parts machine, but put a pipe wrench on the end of the shaft (with some leather covering the jaws) and gave it a nudge. It freed up immediately and spun like a champ, no damage. Something must have been in one end or the other of the main shaft bearings, and I forced it out. Maybe a thread? I never found a danged thing. Maybe yours has a similar problem in the making?
CD in Oklahoma