While you wait for answers, we may have found some information which could help you.
Click here for Sewing Machine Thread Needle
the thread is bunching on underside of fabric it looks like birdnest?
Singer 201 went bang , smelt and now won’t work?
Singer 188K1 presser bar stuck?
Engine revving up ?
Singer zigzag 457 Stylist not threading bobbin/making stitch?
Presser foot is loose?