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Hello to all, I have an inquiry regarding E10 gasoline.

What is E10 actual shelf life if:
stored in boats fuel tank...
stored in appropriate storage container...

Now, same inquiry but using fuel treatment (exa. Stabils Ethanol Treatment etc. etc.).

I am curious due to a forum thread posted by a marine mechanic that states, E10 even with fuel/Ethanol treatment is good for only 60 days and should not be used after that time period.

How does one's home area climate affect E10 (exa. I live in South Florida) mid to high humidity levels in the summer.

Any and all input is highly appreciated...

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I stored my Montauk 17 with 22 gallons of E-10, stabilized, and it was good 5 months later when I had put on a new element for my water separating fuel filter and had a new E-TEC 90 put on. I used that gas with no problem and found no water.

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We have routinely stored over the winter (October - May) with E10 gas and Stabil and have had no fuel-related problems. Still wish we could get real gas and would be willing to pay a premium, but the E10 has not caused any problems.

Tim

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That mechanic's statement seems a bit extreme. Massachusetts here, too, boat stored 6 months over the winter. No problems at all with E10 and Evinrude's 2 + 4. I have yet to see any water in my filter.

John K.

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This is always a lively discussion that I try hard to remain out of. I have no positive feelings toward the use of ethanol in our fuel to any degree but I'll leave you to ponder this.

Auto manufacturers are banding together against the use of E-15 or what some also refer to as E-85. What most of us are using now is labeled as E-10.

If E-15 has all the auto makers fired up and to the degree they will refuse to honor warranty issues if it is used in their vehicles, how is it that E-10 is all that much better?

Most of the small engine manufacturers are now marketing True Fuel in pre mixed containers that has no ethanol and is already mixed with either a 40-1 or 50-1 oil ratio and also stabilized that they highly recommend to be used in their equipment. Stihl and Husqvarna as well as Tecumseh and Briggs and Stratton are all going this route with their small engines and the True fuel is a big seller at the box stores like Home Depot and Lowes.

I just had both my weed eater and chain saw serviced by Stihl because neither would run right. Both required carb rebuilds because O rings and diaphragms were shot and the mechanic handed me a bottle of the True Fuel to use going forward. Go to these companies web sites and read what they have to say regarding the use of ethanol in our fuel.

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There is no "actual shelf life" All gas E-10 or standard non-ethanol unleaded starts to loose some additives in as little as 90 days. It also has a lot to do with how and where the gas is stored. In a closed system like a car the lighter additives won't vaporize off as fast, in an open container like the gas can in the shed the process will be faster.
I have had treated E-10 gas last in my boat, in a partially filled tank, over the winter last 10 months with no water observed in the filter and no damage to my nice new engine. I would not push any gas, E-10 or otherwise past 1 year without pouring some in a glass jar and taking a look. Provided you have no water, no rust or other contaminats, the fuel should be good to use. It will not have the same additives for engine cleaning, performance boost or whatever else they add to fuel these days, but it should run your engine.

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One factor involved in the total answer is the climate.
Heat increases the breakdown of most things and E 10 in particular.
Also of pre mixed gas.