I've got an old ('89) MTD lawn tractor with a 12hp B&S engine, 38" cut. The engine drive pulley has come apart and needs to be replaced. I can find replacements, but my question is how does the old pulley come off? It seems like there is a nut holding it on. Normal or reverse threaded? How do I keep the motor from turning (or will it) when trying to remove the pulley?
Thanks for any replies

If there is enough room between pulley and motor put a pipe wrench on it this will hold motor still for you to get pulley off.

Did you ever get the part off?