Adding Sea Foam to old boat fuel [SOLVED]

I have a built-in 15 gal. gas tank in my boat. The boat has been sitting for about a year and a half and the gas has “varnished” up in the tank. I want to dissolve the contamination and take the old gas to our county recycling location. Can Sea Foam dissolve the contamination?

Notify of

1 Comment
Newest Most Voted
Inline Feedbacks
View all comments
Jim D.
Jim D.
2 years ago

Hi Don. If I understand your question correctly, here’s what I would and would not do: I would not treat the old fuel if you’re going to remove it. After you remove the fuel, add a gallon of fresh gas with a can of Sea Foam or Marine PRO, then just run the engine for about 15 minutes to get the gas and treatment mix working through the motor. If everything seems fine just add 2 or 3 more gallons of fresh fuel and operate as normal. The reason I am suggesting less fuel is to keep a higher cleaning concentration ratio of Sea Foam to fuel working through the tank and engine. Hope this makes sense!