Originally Posted by Aussie Steve
Does sound like an electrical connection gone bad. They can be a real pain,
Sorry but you're going to have to trace the fault, start by confirming that you loose spark when it wont fire (it does crank doesnt it?). id it does from there check for power to ignition system, stator and pickup coil tests when its not working.
Yes it turns over - just no fire. I don't have the right size socket to get the plug out to test that. Thought it was 5/8.