I have a !965 Sea King 8 hp. Fired it up first time in a least 20 yrs.. Runs strong! After I went with a 50 to 1 oil / gas mixture it smoked less but still smokes alot. What do I need to do to make this thing a little more environmentally friendly? After I run it in a barrel for awhile the water is really dirty. The water is really frothy and it also has spots of oil or grease or whatever. There is a film of gas also. I know this is an old motor but I plan on using it to catch fish not kill them. I'm very conscientious when it comes to the environment but I can't afford a newer more efficient motor. What can I do to make this beast cleaner. It's really a cool engine.