Originally Posted By: mez
My lawn tractor engine doesn't shut off immediately. It sputter and then shut off. Any ideas?
Is this a newer machine?
I've experienced this phenomena with several late model, single cylinder and V-twin equipped riding mowers. Most notably was my Cub Cadet 2544 rider. If you killed the ignition at idle it would backfire so loudly it was painful, or it would diesel. If you killed the ignition per Cub's recommendation, which was throttled-up. No backfire, no dieseling. IMO, the condition results from the last bit of fuel working it's way through the engine after the ignition is killed. The hot engine or exhaust lights it off. They've all got fuel cut-off solenoids these days, but this only stops further fuel from entering the carburetor bowl. The bowl is still full at shut-down. If you're throttled up, the extra air leans out the mixture enough where it's not an issue (my opinion). Why it's more common on newer OHV engines I have no idea other than maybe they run hotter.
Long story short, shut the engine down per the recommendation in your Craftsman's owner's manual. I can almost guarantee your problem will stop if you kill the ignition at partial to full throttle.