Good question, Gary. Yes, you can add Sea Foam to gasoline that already has Sta-Bil (or another additive/stabilizer) already in it. It’s safe and effective.

Thanks for the question! Sea Foam cleans fuel residues and varnish that form over time in any fuel system. It’ll help overcome and prevent common problems often caused by residue build up in small engines (like rough performance, hard starting, etc.). To clean residues and varnish in your small engines, add a high concentration of Sea Foam to a low tank of fuel (1:2 ratio of Sea Foam to fuel). Then, run the engine for about ten minutes, shut it off, and let it soak overnight. Start it up the next day and run it for a while.

For small engines, I like to use non-ethanol fuel, and avoid letting the fuel sit in the tank for long periods of time.

As far as ethanol goes, here’s part of an answer from another question:

“Because Sea Foam adds protective lubricity to fuel and fuel system parts, it will always help. Even though Sea Foam will help protect against ethanol and water, be careful not to buy into any false sense of security that a fuel additive is going to completely counter the harmful effects of ethanol, particularly when left in a tank for a long period of time.” (Note: in modern car and truck engines that are built to handle ethanol, there’s no need to worry about ethanol destroying fuel system parts on its own).

Here’s the full question:

https://seafoamworks.com/questions-and-answers/can-you-use-sea-foam-motor-treatment-with-ethanol-gasoline-solved/

Thanks for the question, Kevin. In addition to stabilizing fuel, Sea Foam cleans gum and varnish from the entire fuel system and prevents it from forming. Gum and varnish is often the cause of rough performance or hard starts. Sea Foam will clean it out, helping your generator start and run better.

Thanks for the question, Blaine! Here’s an overview. It depends why you’re using it:

• For preventative maintenance/fuel storage: 1 oz per gallon
• For fuel system cleaning/overcoming a fuel-related engine problem: 2 or more ounces per gallon. To maximize cleaning, add a full can (16 oz) to a low tank (2-3 gallons) and drive until almost empty before refueling.

Thanks for the question. No, Sea Foam does not have ethanol it it. It’s made with a blend of petroleum cleaning and lubricating ingredients. You can use it in any gas or diesel engine. Hope that helps and let me know if there’s anything else!