We may have found other answers which could help you.
Click here for Needle Lower Thread
Presser foot is loose?
Singer 188K1 presser bar stuck?
the thread is bunching on underside of fabric it looks like birdnest?
Engine revving up ?
My CG 500/550 Singer Sewing Machine's bobbin isn't working?
Singer 201 went bang , smelt and now won’t work?