I had this smoking problem in the winter while plowing and thought it was water in fuel but now my GS6500 smokes like crazy approx. 5-10 seconds after I fire it up. It is the a ton of smoke at first then it calms down little only blowing smoke every now and then as I roll on. My 2stoke snowmobile produces less smoke than my tractor! It is definatley burning oil off the exhaust but where do I start to find the problem? It's got 50hrs on it. Any thoughts as to how oil is collecting in the exhaust would be great.