Would a fuel additive work?

[David M]

At work one of our boats is a C-Dory with a 80 horsepower, four stroke, four cylinder carborated Yamaha ourboard. The engine recently started running on three cylinders, so I did the usual stuff to try to get it running on four cylinders. I ended up taking the engine to the local Yamaha repair shop. I was told that with the gasoline that is blended with alcohol, that when the alcohol evaporates it leaves behind a residue that causes the carbs to not function correctly. The solution I was told is to run the engine at least once a week.

Does anyone know of a fuel additive that will prevent alcohol resudue from clogging the carborators?

[svHyLyte]

Try Star Tron Enzyme Fuel Treatment - HOME . I cannot atest to the efficacy other than to say it seems to work for us.

Futher, when taking your engine out of service for awhile, disconnect the fuel line and run the engine until it quits. Then, take the cover off and remove and empty the fuel fliter bowl and dry it with a lint free cloth. Running the engine until it stalls does not empty the fuel filter bowl which, if not emptied, will sit and accumulate water and grow bugs over the winter. Been there, done that, got the T-Shirt.

FWIW...

[mikereed100]

As Forest Gump says, "I'm not a smart man", but I am a little suspicious of the alcohol evaporating and leaving a residue thing. AFAIK there are dozens of highly volatile components to gasoline and I can't imagine that E-10 would evaporate off at such a higher rate as to leave residue, but again I refer you to the above quote.

Practical Sailor has an article on fuel additives this month that does not mention this problem. It does talk about the solvent effects and water absorption and separation, though. They conclude that none of the additives works all that great and that a fuel/water separator, even with outboard tanks, is a better solution. For oxidation stability and detergency they recommend Sta-bil, Star Tron and Techron.

Mike

[AnchorageGuy]

Originally Posted by svHyLyte

Try Star Tron Enzyme Fuel Treatment - HOME . I cannot atest to the efficacy other than to say it seems to work for us.

Most official reports on the Star Tron say it is little more than snake oil. Some additives have an affect and some just make you feel good. I too would be a bit leery of the alcohol claim and try for a second opinion before taking any action.

[Charlie]

Originally Posted by svHyLyte

Try Star Tron Enzyme Fuel Treatment - HOME . I cannot atest to the efficacy other than to say it seems to work for us.

Futher, when taking your engine out of service for awhile, disconnect the fuel line and run the engine until it quits. Then, take the cover off and remove and empty the fuel fliter bowl and dry it with a lint free cloth. Running the engine until it stalls does not empty the fuel filter bowl which, if not emptied, will sit and accumulate water and grow bugs over the winter. Been there, done that, got the T-Shirt.

FWIW...

I always run the engine dry even if I know that we are gign to use it again the next day. The kids don't like it but I had to rebuild a carb once and din't enjoy it. Thanks for the info on the fuel filter bowl didn't even think of that. Nice thing to do when winterizing the boat.

[CaptHead]

Ethanol is an enemy to boats as it readily absorbs water. Take some ethanol, vodka works, and add it to gasoline. Then add some water and watch it absorb into the gas. Another problem is it eats fiberglass fuel tanks and the USCG warns about that as the residue gets into engines and destroys them. I had to change out my carb kit with a new alcohol resistant version and my engine is a 2004. I always ran it dry after use too but the alcohol ate the rubber in the carb anyway.

Good Luck!

[David M]

Thanks everyone. Looks like the best thing is to run it once a week and each time disconnect the fuel hose until the engine burns the last bit of fuel.

[SelkirkWind]

Originally Posted by David M

Thanks everyone. Looks like the best thing is to run it once a week and each time disconnect the fuel hose until the engine burns the last bit of fuel.

That is a lot of work for a small issue. The mechanic is wrong. The issue is that varnish settles out in the jets and metering orifices from the poorly refined gasoline. I recommend Stabil Marine (BLUE not Red!). We have used it for years and never had a problem. Even Walmart carries it (about 18 dollars a bottle, but treats 4 times more gas than Red Stabil and is formulated for plastic tanks).

[Therapy]

Originally Posted by SelkirkWind

I recommend Stabil Marine (BLUE not Red!). We have used it for years and never had a problem. Even Walmart carries it (about 18 dollars a bottle, but treats 4 times more gas than Red Stabil and is formulated for plastic tanks).

I did not know about the "blue".

Thanks.

I will look into it.

[Ike]

Selkirk has it right. Alcohol is a solvent and it "cleans" out all the gunk that collected in your fuel system. On older boats the gaskets in the carb may also be detiorated by alcohol. Additives may make a temporary fix, but the best thing is do a carb rebuild with newer gaskets that are alcohol resistant, clean out the jets and orifices. Also check the fuel lines. If they are more than foru or five years old replace them.

[BassAckwards]

I started using Startron (for diesel) last year in my Westerbeke 30. The engine starts easier, doesn't smoke when cold, and runs much better.

Good article all should read it. I worked 10 years for Mobil Oil Refinery and this information is consistent with what I think I know...

<<The Side-Effects of Ethanol
The first problems encountered with transitioning to E10 is the loosening of sludge from the fuel tanks. Ethanol is a very effective solvent and it will attack varnish, gum, and resins: the sludge that can build up in fuel tanks. Once cleaned off the fuel tank walls this build up leads to poor performance and frequently clogged fuel filters and injectors. The enzymes in Star Tron® will safely break down and disperse this sludge. After a filter change or two the fuel tanks will be clean and boaters can move on the next, more serious, ethanol related issue…
Understanding Phase Separation
Ethanol has a great affinity for water, and will attract moisture from the atmosphere through the vented lines of a marine fuel tank. The water molecules form an electro-chemical bond with the ethanol that is stronger than the fuel’s original bond with the ethanol. Water is heavier then gas so the water/ethanol molecule is dragged to the bottom of the tank and separates from the more buoyant fuel molecules. This is referred to as phase separation and occurs when the water content in the fuel reaches roughly .5%. Ethanol provides a significant boost to the octane rating of the fuel, so when phase separation occurs you end up with a corrosive water/ethanol layer on the bottom of the tank, under what is now substandard fuel.>>



Dealing with E-10 Ethanol Gasoline in a Marine Environment with StarTron