Do you have a repair manual? Maybe there is something needing to be adjusted. I can sympathize but I can't advise much. I have a big honkin' Consew walking foot that gets thread tangled up in the shuttle shaft... To get the thread out you have to take off the shuttle and pull out the thread. One time it too me a month to get the thing back in time - I should have taken it completely apart and put it back together. I've fought with that machine for 10 years now and I can time one pretty fast. Last week I wanted to use it and figured out that one of the shuttle shaft screws worked it's way out and went AWOL. I would try to find a manual and see if there is some adjustment you missed. Maybe that is what was really wrong with the machine in the first place. Does it turn with out a needle in it? It is also possible that there is something wrong with the machine in another place. I've been saving up my problem sewing machines for a sewing repair class I'm wanting to take. Some times the LSMR guy is what you have to do - but if it happens again you have to take it right back... sigh