Fuel smoke and fouled plug

Nick I said

open system as of now. I dismissed crankcase ventilation as a culprit with having the one bad plug.

Click to expand...

I here what your saying - the one plug deal.
I will tell you that engines that are not vented properly can and will do strange things. As $cheap and simple as it is to add it to your engine it would be one less issue to eliminate. Cant hurt and you my like the outcome.