I have cleaned this singer 500, I swear it had sand dumped in it. It was hard to turn the dials on the front. It is clean now but I can not get the calm to go back in. It pops out and will not stay in. I set the front dial to B and the back dial to L and special, it’s the #1 cam. The dials trun much better.I took the motor out cleaned the sand off and greased the worm gear. I don’t know what else to do.
Thanks