I have Husqvrana lawn tractor with a Kohler Courage 21 engine. The engine died abruptly the other day while mowing. It won't start and cranks very hard, keying the ignition switch just moves the flywheel a few teeth, I have to do that several times then finally it makes one complete revolution then refuses to turn again and I have to repeat the process. Carb either pops or backfires when it turns through the complete cycle. Have air cleaner off so I can hear and feel air being pushed out the carb. The big key holding the flywheel is intact, but I don't know how to check the internal woodruf key on the crank.
Battery is good, as is fuel and spark. I am guessing this is something valve related, but something more than just needing valve lash adjustment. It was running fine right until it died, then nothing.
