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Have I used untreated gas that old in the past without apparent issue? Yes. I've read in many places that gasoline will begin to degrade within 30 days. I don't know how much I'm concerned about 30 day old gas, but 90 days can be an issue. I've had machines (lawnmower) run poorly or not at all because of old fuel. A carb rebuild had to be done because I left fuel in it all winter.
During the winter, I always put a fuel stabilizer in the gas when I get it.
Is it the result of the ethanol mix that's so prevalent these days? I don't know.
I buy non-ethanol gas (even at increased cost) for my small engines (ATV, snow blower, string trimmer, mower, tillers). During the lower-use months, I always put fuel stabilizer into the can when I fill it.
As for condensation, that is possible, particularly if you live in a humid area. The same thing can happen in vehicles under certain conditions. However, if the gas can is full when it's stored away, then the likelihood of humid air getting into the can is greatly reduced and condensation is less likely.
You might try running some Seafoam additive in the fuel if the machine is still running poorly.
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Ethanol is hygroscopic, so yes. The moisture the ethanol absorbs an cause all kinds of problems. I used to leave my appliances that had metal tanks full of fuel in the off season to prevent rust...but with Ethanol fuels they could rust anyway (I'm kinda glad they all have plastic tanks now). Anyway, modern gas is crap, I wouldn't leave it in anything very long, though the treatments like Sta-bil and Sea foam really do seem to help.
I started with absolutely nothing. Now, thanks to years of hard work, careful planning, and perseverance, I find I still have most of it left.
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Every time I fill my gas can for my small engines, I mix in fuel stabilizer and ethanol treatment.
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01-11-2018, 03:10 PM
(This post was last modified: 01-11-2018, 03:10 PM by tomsteve.)
i think metal gas tanks, even with pure gas youll get condensation.
with ethanol gas, condensation/water causes phase seperation
http://www.lcbamarketing.com/phase_separ...l_blen.htm
its possible to get pure gas still and good to run in small engines that dont get used often
https://www.pure-gas.org
typically marinas and airports sell pure gas.
seems places that sell racing fuel,too.
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Another "yes" vote.
There is one place in town that sells ethanol free gas.......the farmers co-op. I get that for all small engines.
But ethanol is only a part of the story. As EPA is regulating small engines more and more they are being engineered and tuned to tighter tolerances. So the "I used to leave gas in my lawn mower all winter and it would start on the first pull every time" is often true...but the change is both a gas problem and an engine problem. So now instead of using an extra pint per year to mow my lawn all summer and keeping a lawn mower for 10-15 years, mowers are dying at 4-5 years and being landfilled (probably too often with gas and oil still in them). In somebody's world that makes sense.?.?.
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PS to add: If I have small engine gas's more than 2 months old I funnel it into a full tank in one of the cars. That little isn't going to make a difference.