I had a similar problem once with my Brother. But mine was my own fault being new to sewing and not having anyone around to teach me about cleaning my machine. I fought with a JRR for my niece using words that would embarrass a sailor. After I finished I figured I could not do any more damage to my machine then it already had so I got brave and removed the screws that held the plate down and discovered a whole lot of lint around my feed dogs keeping it from moving properly. I know this is more then likely not your problem but just wanted to let you know I know how you feel about having to pull your quilt through.