I received a a free Craftsman mower, (917.250520) and it was seized, dirty, and didn't run. Now it runs and even mows. Still needs a lot of work, but getting there. I have two questions. The first question is sometimes it turns over, sometimes the starter just spins, is that the solenoid? Second, I have a 20 hp Kohler Commander, can I get a muffler for this thing?