Hello, I have a 1966 3.9HP one cylinder merc, I am mixing my fuel 50 to 1 but I do not think it has the right spark plug. I was wanting to ask if anyone knows the plug I need and the spark gap setting also could my fuel be to rich for this year?. I have read that older motors should be run rich, It is putting out a little more smoke then I think it should but seems to run good. thanks for any help anyone can give.
