I think about the only thing you can do is rule things out. If you have another cluch laying arouns anything just one to put on the sled put it on and try it. I was 100 miles from my cabin and my wife said "this thing is noisy all of a sudden" I told her to ride it as far as she could. She made it halfway and we stopped for lunch (we were with our club on an overnight trip) we walked in and she said it had been running badly for the last mile and quit when we pulled up to the restraunt(sp?). That is all she wrote, luckliy we had a chase truck (who wouldn't with 50 sleds) and we just loaded it up and doubled up, that was a pain. Ohh anyways back to the answer, if you don't have a spare, I may take it apart and have a little look make sure the pto bearingon the cranks is not blue, I believe it was the bearing at the base of the rod. Kevin