We may have found other answers which could help you.
Click here for Sewing Machine Repair Singer
Bobbin won't wind?
the thread is bunching on underside of fabric it looks like birdnest?
Engine revving up ?
Singer sewing machine 626 kno?
1965 Singer 275k sewing machine foot pedal?
Singer zigzag 457 Stylist not threading bobbin/making stitch?