How much Sea Foam is too much for an old car [SOLVED]

Will a gasoline engine run on 100% Sea Foam? How much Sea Foam is too much? I would like to run Sea Foam through a car that has been sitting for 20 years. I want to run as much Sea Foam as possible to clean the carb as much as possible, but I don’t want so much that it won’t run.

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Jim D.
1 year ago

Good question, Michael.

First, a gasoline engine will not run on 100% Sea Foam (though a diesel will!).

I would add 2 cans of Sea Foam High Mileage to a low tank of fresh fuel (1-2 gallons). Then, run it until almost empty before refueling. That concentration will be plenty strong. The highest ratio we recommend is 50/50 Sea Foam to fuel (guys will use that ratio in a fuel injector cleaning machine). But 2 cans in a low tank is enough in your case.

Here’s a response to a similar question to a gentleman who had a 1967 Firebird that sat for 15-18 years. His vehicle wasn’t running yet, but these steps would probably help you as well. I’d recommend running a can of Sea Foam Spray down the carburetor throat.

“Here are some ideas to consider: 1) It would help to add half a can of Sea Foam High Mileage to the oil crankcase to reliquefy old oil residue, 2) a can and a half of High Mileage to a low amount of fresh tank fuel (start with only a gallon or two in the tank), 3) a can of Trans Tune down the ATF filler neck, and 4)  I’d remove the spark plugs and spray a healthy burst of Sea Foam Spray into each chamber, crank the engine 4 or 5 times to pull the Sea Foam mix into the carburetor circuits, then let it soak overnight before starting.  After you get the engine running, spray the rest of the can of Sea Foam Spray down the carburetor throat (clean intake valves and chamber areas – see can instructions).”

Let us know how it goes!