Thanks for the question, Bill! We get a few people asking about Sea Foam in furnaces like that each year. Yes, you can use Sea Foam in your diesel storage tank. Add 1 ounce of Sea Foam per gallon in the tank.

Hi Jacob,

Thanks for the question! Yes, Sea Foam Motor Treatment is safe and effective in any gas or diesel engine, including your two strokes.

You can use up to a 1:2 ratio of Sea Foam to fuel. Here’s what I’d do:

• Add the Sea Foam to a small amount of fuel (8-16 oz of fuel).
• Run the engine for a few minutes to draw the treated fuel through the system.
• Let it soak overnight.
• Run it again for a few minutes before storing it for winter.

Thanks for the question, Raymond. Sea Foam does not have a lifespan – you can definitely still use a can that’s two or three years old!

Thanks for the question, Terry!

You do not have to fill up the tank after adding Sea Foam. That plan will work great in your motorhome. Just make sure to add at least 1 oz of Sea Foam per gallon of fuel in the tank. A second can wouldn’t hurt if you want to get some extra cleaning power in addition to stabilizing the fuel and protecting the fuel system.

Thanks for the question! Adding Sea Foam to your mower’s tank will help prevent the fuel from breaking down and help prevent varnish from forming in the fuel tank. Varnish is a very common cause of poor engine performance in small engines like mowers, so Sea Foam in the gas tank during storage is an easy way to prevent issues.

You’ll want to add at least 1 oz of Sea Foam per gallon of fuel in the tank. However, it’s okay to add more than that. In fact, a higher concentration will do a great job cleaning any varnish in the fuel system.

Here’s what I’d do: add about ¼ of a can (it doesn’t have to be precise). Then, run the engine long enough for the treatment to work through the entire fuel system (about 5-10 minutes of idling).