sewing machine is jammed wont go up and down?

First of all turn the balance wheel backwards that might free the jammed thread, failing that take out the bobbin case and undo the two clips holding the raceway in if you have a side loading or front loading bobbin case, unfortunately you have not said what machine you have, drop the gate down and take out the raceway and look for the stuck thread.

drivewithken
November 2009