I have a Singer 401a, and I’m having some difficulty with it groaning and halting. Essentially, when the lever is down, the machine catches on something and I have to manually release it by turning the handwheel myself. I can feel it uncatch, but I’m not sure what exactly catches. It makes a weird groaning sound. I can usually manually get a stitch or two in there, often with birds nesting, but get past it. Once the machine gets going, it can stitch well. I’m 100% sure the top thread is threaded properly as well asthe bobbin. I’ve tried changing the top tension and switching out a needle. There’s no obvious gunk in the machine. I’m oiled up all the parts in the manual and greased all of the gears. This happens when I’m sewing lightweight nylon but also can happen with other materials. Any ideas?
