Sounds like something is in a bind. Can you spin the motor over by hand, ie the flywheel? Just elimate the possibility that the motor is locked up. Second pull the EZ start motor off and try it and see if the motor spins over. If it does, then it sounds like a gear may be trashed inside the EZ start assembly.
In that case... ditch the EZ start and get a pull start. I hated mine on my rustler. Darn one way bearing would die every other day and the battery never had enough juice to heat the plug enough and spin the motor, IMO.

-bryan