Tried a search and did not find anything, so - - has anyone tried or currently use Marvel Mystery Oil in their boat? What about HP motors..Thanks,

I don't know about my boat but always in our plane and in my KTM RFS i swear by the stuff....i never really thought about putti.g it in the boat...i've asked alot of mechanics and they say it not gona hurt anything...valves love the stuff

I was told by old Marine guy to pour in a couple of oz directly into the carb while flushing, help out the valves and guides but does cause white smoke out the exhaust! On a FI engine, not sure where you would access to pour it in and what it would do to your sensors?

I run a qt per every 80 gal of fuel and now staring to run about a 1/2 qt in each motor per oil change. It's recommend and sure can't hurt with the bad fuels we run through today.
Just my opinion

I believe tranny fluid serves the same purpose. Info came from a old time mechanic.

I use it in every tank of gas, was told this, by a guy on one of the boat race teams. Like J.B.Marshall said, with the poor quality of gas today, it sure can't hurt.

I have been using it for about 20 years.Here ya go:http://www.marvelmysteryoil.com/inde...te/wheretobuy/

I used it one to free up a motor that wouldnt turn over but that was the one and the only time.

My question is what are you trying to achieve by using it?

It works great to lube the valves which basically run dry. It also puts some lube on the top compression rings. I like the stuff and Wallys has gallons for about $10.00
I don't use it in the oil though, I run synthetic.

If you are dumping this in your gasoline what would the effect on octane be? I would hate to cause detonation.