Home Forums Hunting & Shooting Hunter's Campfire Gas additive for 4 stroke outboard????

I've just got my 25 horse Honda 4 stroke back in the water after sitting up 4 years.The carbs were drained before storeing and it is running remarkably well but doesn't idle very good and seemed a little sputtery a couple times today.

I will change the plugs but should I use any kind of gas additive to help clean the carbs? I only use 100% gasoline always.

Seafoam.

Just discovered that stuff about a year ago.
Like it much.

Seafoam is very well thought of around here and I won't disagree with that suggestion. I've never tried it though. The fuel injector cleaner/fuel system crud remover that I'm sold on is Chevron Techron. I can't say that it's any better than Seafoam but I never found a reason to try anything else.

Essential Lube. It is like a Jesus miracle in a can.

Either of the above should help.

Do the plug change and see if that helps. Seafoam or Techtron won't hurt, but I'd try one thing at a time to find out what cures the problems. I'm not sure if the carbs on these engines are similar in design or not. I have a larger motor, a 90 hp, and it has a long thin passageway in each carb which can become blocked by corrosion effects if water gets into the carbs. I suppose it could also suffer from other crud. In any case I had to do an overhaul on mine the year after it had ingested some quantities of seawater after the boat swamped. It was funny how little crud it took in those tubes - one in each of the four carbs- to give the engine trouble running well; and not all four were plugged. The Honda dealer tech I talked to diagnosed the problem over the phone and admitted that as being a somewhat flawed part of the fuel system. That said, my motor is a '99 and has over 1000 hours on it with carb corrosion a single time being the only issue it has ever given me; well, that and 5 quarts of oil every year.

Roger that.

Techtron

Same here - Seafoam!

Yep. I just used it again in a 4 stroke Troy Built weed eater that had been in storage for over two years. It smoothed up in just a few minutes of running. I've used it in at least a half dozen various small engines & only one needed a carb rebuild.

I take it when you say 100% gasoline you mean ethanol free. Unless it's Blue Fuel or 100LL, automotive gasoline still has shelf life problems.

Seafoam is a good choice.

Another Seafoamer...