We may have found other answers which could help you.
Click here for Sewing Machine Needle Timing
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 188K1 presser bar stuck?
Singer 201 went bang , smelt and now won’t work?
What size needles can I use for my Singer 39a3?