Thanks to the advice and help of members here, I picked up a 1920 31 15 in excellent condition. This machine sews great, but has a clutch motor the size of a large water melon, just a bit too much pressure and it takes of like a rocket. I am looking at several servo motors to replace it with, Goldstar, Toledo Ind and ConSew. They are all about the same price, look the same, seem to be the same motor, 550 w 3/4 hp Thanks for any advice or experience with any of these motors