Treadle belt slipping
Hi. I have a Minnesota Model A treadle. It's my favorite machine by far. I had to replace the treadle belt when I got the machine early last summer. It sews beautifully on thinner fabrics but the belt slips when I tried to hem jeans that were too long.
The belt doesn't fit down into the groove on the pulley but seems to sit on the top. Whenever I try to stitch heavy fabrics, the needle stops and the belt slips allowing the treadle to keep going but the needle doesn't move. I'm not sure I'm explaining that clearly.
I hesitate to shorten the belt yet as I cannot make it longer if that isn't the problem (lol). The belt is very stiff. Should I oil the belt?
Another issue I have is the needle often gets stuck in whatever I'm sewing and pulls out of the needle bar. I'm sure it's because I cannot get the screw tight enough to hold it in place. I tighten it as much as I can with my fingers but I do have arthritis. I could use pliers but worry about stripping something. Anything I could try before I use those?
Thanks in advance!