How can I mend my Frister & Rossmann sewing machine?

My Frister & Rossmann cub sewing machine has worked well for years. It has now suddenly gone berserk working at high speed even without depressing pedal. Can you help?

J Fry, November 2023


done
There's probably a capacitor in the foot control that's gone short. Plenty of advice available online

Ffhh, December 2023
link Click here to see other fixes for Frister & Rossmann.