Stitching Problem On Singer 15-91
I can't figure out what the problem is with my singer 15-91. It makes absolutely wonderful stitches but I can only sew about 10 blocks together before it jerks the spool and makes a birdsnest on the bobbin side. Sometimes it jerks the spool so much that it winds thread around the spool holder. Sometimes it breaks the needle thread and other times it does not. I put in a new needle, I rethreaded the upper part, I took out the bobbin and checked the manual to be sure it was in correctly. I just don't know what else to do. I am thinking I might need to take the tension apart but that scares me a little bit even thought the manual has fairly good directions. Does anyone else have this problem or know what might be the solution. I dearly love sewing on this Singer and I don't want to give that up but it is very disgusting to be sewing along and this happens. Here is a picture of what the underside or bobbin side looks like. The top part is normal.