We may have found other answers which could help you.
Click here for Bobbin Thread PullPresser foot level, needle and thread guide have fallen out?
Toyota SL3404D Overlocker leaving big loops?
Singer zigzag 457 Stylist not threading bobbin/making stitch?
Parts spares?
How to switch on light of sewing machine?
How can I mend my Frister & Rossmann sewing machine?