[Al Skierkiewicz]

I am guessing here, but as that motor heats up the bearing clearances probably start to close down and eventually seize the motor shaft. I am guessing that if you take the motor out after it cools, it will likely rotate fine. However, once the shaft has seized, I would only use that motor in an emergency. The bearings are damaged and the high heat has boiled the lubricant. Even if it works, I wouldn't trust it any longer.