[john hall]

I replaced the plug in mine last year. For some reason I think it had a flange with an O-ring. If so it wouldn't be NPT, possible NPS, not certain. I'm pretty sure mine came from Cub Cadet Warehouse, don't know if Cadet still offers it or not. I remember while draining the oil that it would probably be less mess to either pull the engine or drop the deck and mule drive. Some re-engineering is certainly in order!