You can try using dental floss though the tension disks to remove any broken threads in there. Sometimes a clear computer button can work too. I once had thread wrap around the hand wheel in the back too. I had left the spool up there that I wound a new bobbin on.
I also had a thead get stuck in a slot on the cone the thread comes on. (the one for storing the thread ends) and it kept the wheel from turning because the thread was not coming off the spool.
Oh and one more thing to check. If you have ever broken a needle off into the machine a tiny bit of the tip can be removed with a magnet.
Last edited by RedGarnet222; 04-27-2014 at 12:50 PM.