How long does ethanol free gas last?

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The gas in my Can am has been in there since august. Even with a double dose of stabil 360 it still went rank. All I can get is E10 but I can buy race gas in 5g cans. Wondering how long the ethanol free race gas lasts.
 
Is that carburated? No idea but if the tank isn't sealed, I can imagine it oxidizes somewhat. I've had 4,5 even 8 year old E10 in the tanks of cars that still ran fine but they are fuel injected.
 
Originally Posted by atikovi
Is that carburated? No idea but if the tank isn't sealed, I can imagine it oxidizes somewhat. I've had 4,5 even 8 year old E10 in the tanks of cars that still ran fine but they are fuel injected.


Ive not gone that long but I can have 6-12 month old gas in my truck.

In OPE, depending upon how the fall shapes up with timing of buying gas and how many times I need to mow/blow, its quite likely that a tank will go from Sept-May. Never had an issue with it going bad.
 
Originally Posted by atikovi
Is that carburated? No idea but if the tank isn't sealed, I can imagine it oxidizes somewhat. I've had 4,5 even 8 year old E10 in the tanks of cars that still ran fine but they are fuel injected.

Fuel injected
 
Originally Posted by atikovi
if the tank isn't sealed, I can imagine it oxidizes somewhat. .

The gas tank is sealed. The utv has a charcoal emissions canister just like a car. Our califilornia gas is just junk.
 
I wish I could answer your question, but it obviously doesn't take too long. Just yesterday, I was in my shop and saw the weed wacker sitting there. On a whim, I gave it a couple of pulls (more than normal), and I got it to run.
But it actually ran terrible. I didn't run it too long, but I'm pretty sure it was from stale gas. I buy alcohol-free gas for my lawn equipment and I purchased this gas at the end of summer last year.
Next weekend I'll have more time and I'm going to burn all the old gas out of it.
 
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I have the same problem you do and I run E0 only in my power equipment.I have started using 100LL AVGAS in my 2 stroke equipment all the time and use it to flush out my mowers and 4wheelers when they are put away for the winter.The guy at the airport claims it's good for 10 years but I take that with a grain of salt.Even the pump E0 is only lasting 3-4 months before going stale in my experience.I tried Stabil ,Seafoam,Marvel ,etc with no luck.I did have some saw gas to last thru the winter with echo oil in it,had a can of straight gas beside it .The straight gas was stale ,both were bought at the same time.After seeing that ,I began using a 2.6 oz of 50:1 oil in 5 gal of gas all the time during season then flush in winter with the 100LL.I would expect racing fuel would last as long as AVGAS.It is about $3 per gal higher than AVGAS here.
 
Originally Posted by Chris142
The gas in my Can am has been in there since august. Even with a double dose of stabil 360 it still went rank. All I can get is E10 but I can buy race gas in 5g cans. Wondering how long the ethanol free race gas lasts.


You realize that 5 gallons will cost about $50 in the PRC?

And the seller is required to keep records of the purchase?

For future inspection by the STATE?
 
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Originally Posted by Chris142
All I can get is E10 but I can buy race gas in 5g cans. Wondering how long the ethanol free race gas lasts.



https://www.sunocoracefuels.com/tech-article/storing-vintage-collector-muscle-cars

We've heard stories about cars that were originally filled with Sunoco race fuel that started and ran without draining the fuel - decades later!
We don't suggest that those stories are typical, but we do know that our fuels will last a long time when properly handled.


https://www.sunocoracefuels.com/tech-article/octane-stability-high-octane-vs-low-octane-fuels

The components used in Sunoco race fuels are very stable and can retain octane in excess of 2 years when properly stored.

87 octane fuels tend to be less refined and contain more unstable hydrocarbons.
As the months pass during storage these unstable components react to form gums,
varnishes and lower octane hydrocarbons.
As a result the octane can decrease within months for 87 octane fuels, especially when stored under less than ideal conditions.
93 octane fuels are more refined and contain more stable hydrocarbons. These stable hydrocarbons can last 2-3 times longer than 87 octane fuel.
Even in proper storage 87 octane gas can start to degrade in 3 months, 93 octane fuel should last closer to 9 months before degradation is noticeable.
 
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So my local Stewarts (a quick shop that is known for milk & ice cream, especially the Death by Chocolate) sells E0 gas at 93 octane. What is the difference between that and Sunoco race fuels?
 
Originally Posted by Donald
So my local Stewarts (a quick shop that is known for milk & ice cream, especially the Death by Chocolate) sells E0 gas at 93 octane. What is the difference between that and Sunoco race fuels?

Yeah Stewarts is very serious about E0 gas.
 
Originally Posted by user52165
Originally Posted by Chris142
The gas in my Can am has been in there since august. Even with a double dose of stabil 360 it still went rank. All I can get is E10 but I can buy race gas in 5g cans. Wondering how long the ethanol free race gas lasts.


You realize that 5 gallons will cost about $50 in the PRC?


Still cheaper than my plugged up injector was.
 
Ethanol free will last quite a while, 6 months+. My 2 stroke snowmobiles sit from March to December with gas in them. And that gas gets used in them, no draining. These are not stock high HP 2 stroke engines. I NEVER put stabil or seafoam or any of that crap in my fuels.

My RZR has commonly has gas in it for 4-6 months at a time before it gets used up.

BTW, you are already using E10 and you are adding more alcohol/naphatha to in by adding stabil? Thats probably why your gas is crap.

BTW AVGas is an EXCELLENT fuel. It will last a VERY long time. We use it in the very modified, high compression, high boost 2 stroke engines. Price varies greatly, but an airport near here had it for $4.19 a gallon last time we needed 50 gallons.
 
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Things are different out here.

Ethanol free stations in CA:

https://www.pure-gas.org/index.jsp?stateprov=CA 26 stations

Ethanol free in WI:

https://www.pure-gas.org/index.jsp?stateprov=WI 960 stations

With 7 times as many people, compare the stations.

Madison, Green Bay OK, but not Milwaukee - why??

CA gas must be refined in CA, can only be sold in CA, and we cannot import any gas from other states.

Boutique formula.

And as Chris said, it's crap.

Illegal to use ethanol free for general purpose. Boats, planes, racing, off road only. And strictly enforced.
 
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Originally Posted by user52165

Madison, Green Bay OK, but not Milwaukee - why??


Milwaukee is in a air quality zone where I believe they require re-formulated gasoline. I'm not an expert though, but i know when you cross the county line gas gets more expensive.
 
Yes, here in Southeastern Wisconsin there is a six-county EPA nonattainment area where only RFG is sold, even at the Milwaukee Marina. There are also areas where local municipalities mandate the sale of RFG.

Non-RFG has not been sold in Southeastern Wisconsin since 1995.
 
No matter what gasoline you buy, it's all going to degrade depending on how open to the atmosphere it is.

Like said, the more sealed the fuel system, the longer it lasts. Marine applications don't fare so well with it given their vented fuel systems. Same with lots of outdoor power and recreational equipment.

The vast majority of gas stations in my area have sold nothing but E10 for over 25yrs now. Kept in sealed tight storage containers, it lasts a long time. Like upwards of a year maybe.

Lots of stations offer what they market as "recreational fuel" now, which is 91 octane ethanol free gasoline. Problem is, it's like $0.75 more per gallon than E10. I do buy it for my OPE.
 
It appears to me it can last a very long time or not a long time at all. I bought an old jetski with 5 year old gas, sitting outside 5 YEARS in Minnesota and it was still good. I think it depends upon #1, a very well sealed gas tank and #2 the original blending being water free.
 
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