Can I add Sea Foam to clean carb jets if there’s another gas treatment in the gas tank? [SOLVED]

Thanks for the question!

Yes, you can add Sea Foam if there’s already another gas treatment in the tank. If fuel varnish is the problem, Sea Foam will help clean it up and help overcome the running problems. The best way to do this is to create a high concentration of Sea Foam to fuel.

Here’s how to do it:

• You can either drain most of the fuel, or add a larger amount of Sea Foam. If draining the fuel tank isn’t too much trouble, do that and add some Sea Foam and fresh fuel – create up to a 2:1 ratio of gas to Sea Foam (example: 8 oz of Sea Foam in 16 oz of fuel). If you don’t want to drain the fuel, add a full can of Sea Foam to the fuel tank. The high concentration works much better and faster for cleaning than a low concentration.
• Start the engine and let it idle for 10 or so minutes to allow the Sea Foam mixture to flow through the carburetor circuits, then shut off the engine.  [If an engine won’t idle, remove spark plugs and crank or rope pull the engine several times to draw the concentration through the carburetor circuits.]
• Let the engine sit and allow it to soak overnight.
• Run the engine after the soak period.  Once the engine has idled for at least 5 minutes, add more fresh gasoline and let it idle for another 5 minutes. Then operate as normal – more engine compression and heat will increase the rate of cleaning.

Any engine that suffered from varnish buildup should run noticeably better, while the remaining Sea Foam in the tank will continue to clean as you go!