Thread: SeaFoam

My 10yo Mariner 25hp is hard to start and idles very rough. Runs great at 30-100% throttle. Some have suggested seafoam. How do you apply it? Use it? Thanks.

You might be able to clear it up a lot by doing a de-carb. Here are the instructions. Decarbing Your Engine- The Process-HOW AND WHY - iboats Boating Forums

Originally Posted by IBNFSHN

You might be able to clear it up a lot by doing a de-carb. Here are the instructions. Decarbing Your Engine- The Process-HOW AND WHY - iboats Boating Forums

Thank you sir. That was very informative.

I'm a believer in the stuff.

i am a believer two

I have used it for several years and it is good stuff

Good stuff. I have used it for years too and haven't had engine problems since I started using it.

Thanks guys. I went out this morning with new Champion Marine plugs and it made a world of difference, cranked right up shifted into gear with no bogging but after several stops and starts, it acted "fouled" again. Going to treat with seaform next.

I am a die hard SeaFoam believer too. Good stuff. I use it in all of my 2 stroke motors. Chain saw, weed wacker, leave blower and outboards. (It is good for four strokers too) You will see a HUGE difference in how your engines idle and respond to adding power. They throttle up much better. In addition to keeping the carb clean, it acts as a fuel stabilizer. I also use SeaFoam Deep Creep to keep linkages lubed and clean. If you fog your engine at the end of the season, (I run mine all year) you can use Deep Creep to fog. I think Deep Creep is regular SeaFoam in an aerosol can. Not positive though. You can buy SeaFoam at most auto stores. The best price I have found so far is Tractor Supply. You can buy it in a gallon can there. It is well worth the price. Try it!

One more thing about SeaFoam. Don't over do it. More isn't better. The directions say one ounce per gallon. Stick to that. It will cause your engine to put out white smoke if you over do it.

Also, if you are having idling problems try some premium gas with the SeaFoam. I usually use mid-grade, never just regular and I occasionally will fill up with premium. All of my engines idle very smooth.