Re: too rich fuel mix?
You are correct JM. Oil formulated exclusively for outboard, or water cooled engines is not meant to be subjected to the same amount of heat that air cooled engines see. It can loose its lubricating qualities just as any oil can if run above its design operating temperature.
There are oils made for both applications and it says so right on the container. Ask your friends why the oil companies make two different types of oil if they believe there is no difference.
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