fuel additives?

does any of you all add some kind of additive to your fuel such as sea foam or ring free? if yes, why? and if something else (other than outboard motor oil) what? and why? thanks in advance for your input!

[phatdaddy]

not on a regular basis, but i usually use seafoam every forth or fifth time i fill up(half a can). i am not a big fan of fixes in a can, but i think it helps the 2 strokes idle better. i also add sta-bil in the fall because the gas turn over is less than summer.

[spareparts]

i usually don't belive in "tune up in a can", but I do use ring free/carbon guard in every two stroke, and I can personally testify to the rewards of running seafoam in a fourstroke engine. Last Yamaha class I was in, the instructer said he ran ring free in every tank, in every vehicle he oowned( of course he gets a discount on it) car, boat, motorcycle, etc. I checked with the auto parts store to price techron( the additive in ringfree and carbon guard), believe it or not, its cheaper from Yamaha or Merc for the concentration levels required. On my last two trips to Fl, I ran seafoam on one trip, and didn't on another, no other changes to the van, picked up 1.5 mpg when running the seafoam. The local water taxi runs ring free in every tank, 3000 hours on a pair of fourstroke 150 Yamahas, no engine issues at all, checked the valve clearnce after a shock treatment, all valves within spec.

[randlemanboater]

Sta-bil is the only thng I have ever used. It seems to work well for stopping carb gum while stored.

[Bygracealone]

Skools mentioned to me that Mystery Oil is good to use every now and again...

[macojoe]

I use Mystery Oil as my fogging oil, and Seafoam as a Decarb, and add it a few times a season.

I have never been a believer in Liquid rings or other Mechanic in a bottle gimmicks but I am a true believer in seafoam. I now use seafoam every other tank and in the winter I use it in every tank for condensation and crap gas because I dont run my boats that much in january and february . I think it makes my old 2 strokes run smoother .A friend of mine who works on outboards says that Techron and Ringfree et all is probably just as good and that if you buy chevron gas it already has techron in it..Frank

[Hammerhead]

I've been using seafoam (once a month) Marvel Mystrey Oil ( add some during oil changes) and ring free (add to gas every oil change in all my motors,..for years. I notice the benifits the best in my 1800cc Honda Vtwin bike.

An ol'wench I knew decarbonized his motors with ajax mixed in water....right down the intake at a high idle. Chunks of stuff would come out in the exhaust. I dunno how good that actually is for a motor tho'. Any thots'?