I think the problem Wiz had with his machine was there's 2-springs that hold the stitch length foward & when one breaks that's what'll happen.They are great machines & will handle up to 3/8" max,so they are good for chaps,upholstery sewing.
We rebuild & sell alot of them they are alot like the 226 Consew & what's nice about them is the feet are cheap since so many other machines use them.
So don't be afraid of it,try it out,if it's a 563 that's a good price!