Best Fuel Preservative for Pure Gas ???

I am curious why some run premium when their small engines only require regular gas?

Cummins12V98 wrote:
I am curious why some run premium when their small engines only require regular gas?

Simple. Most premium fuel is also ethanol free gasoline.

In bigger engines the benefits go far beyond not having gummed up carb’s, the net cost per mile is lower running premium gas than regular gas.

The increased fuel mileage exceeds the increased cost per gallon.

JaxDad wrote:

Cummins12V98 wrote:
I am curious why some run premium when their small engines only require regular gas?

Simple. Most premium fuel is also ethanol free gasoline.

In bigger engines the benefits go far beyond not having gummed up carb’s, the net cost per mile is lower running premium gas than regular gas.

The increased fuel mileage exceeds the increased cost per gallon.

Someone smarter than me can please explain the above is simply not true.

JaxDad wrote:

Cummins12V98 wrote:
I am curious why some run premium when their small engines only require regular gas?

Simple. Most premium fuel is also ethanol free gasoline.

In bigger engines the benefits go far beyond not having gummed up carb’s, the net cost per mile is lower running premium gas than regular gas.

The increased fuel mileage exceeds the increased cost per gallon.

Premium gas doesn’t increase fuel mileage. Octane isn’t a measure of energy content, it’s a component that reduces the premature ignition of the fuel/air mixture from engine compression (like a Diesel). High performance engines run higher compression so premium fuel benefits them. Running premium in an engine that doesn’t need it has no benefit and can have negative consequences of increased carbon build up in the engine.

Most premium fuel is not ethanol free, but most ethanol free fuel is premium.

Cummins12V98 wrote:

JaxDad wrote:

Cummins12V98 wrote:
I am curious why some run premium when their small engines only require regular gas?

Simple. Most premium fuel is also ethanol free gasoline.

In bigger engines the benefits go far beyond not having gummed up carb’s, the net cost per mile is lower running premium gas than regular gas.

The increased fuel mileage exceeds the increased cost per gallon.

Someone smarter than me can please explain the above is simply not true.

Me too, I would like to see some proof of cost over cost. High octane fuels are needed for high compression motors to prevent pre ignition, Knock. Here. where I live at high altitude, low octane (85) ethanol gas gives equal mileage to 91 pure in vehicles. Cant see a difference in performance either. SDDOT.GOV results.
Back to OPs question. Ethanol fuels absorb moisture from atmosphere as ethanol is a dessicant and the resulting water contamination can be a serious issue.
Ethanol is an alcohol 1 of 7 miscibles that dissolve in any amount of water.
So your beer may be a near beer (.05 %) or an 190proof Everclear. Thats what ethanol is is a highly distilled grain alcohol. It loves water and can turn your gas into 10 % near beer.
I use 87 octane 10% ethanol in regular drivers with sealed tanks, 91 no ethanol in seasonals like boat , snowsleds, mowers, Harley, and 100LL av gas in all 2 cycle tools.
Never a stabilizer. Some sea foam for fun at beginning of the season for that machine.

Jkwilson, thanks!

SDcampowneroperator wrote:

Here. where I live at high altitude, low octane (85) ethanol gas gives equal mileage to 91 pure in vehicles. Cant see a difference in performance either. SDDOT.GOV results.

Not true, see this site.

SDcampowneroperator wrote:

Cummins12V98 wrote:

JaxDad wrote:

Cummins12V98 wrote:
I am curious why some run premium when their small engines only require regular gas?

Simple. Most premium fuel is also ethanol free gasoline.

In bigger engines the benefits go far beyond not having gummed up carb’s, the net cost per mile is lower running premium gas than regular gas.

The increased fuel mileage exceeds the increased cost per gallon.

Someone smarter than me can please explain the above is simply not true.

Ethanol fuels absorb moisture from atmosphere as ethanol is a dessicant and the resulting water contamination can be a serious issue.


It loves water and can turn your gas into 10 % near beer.

That ‘near beer’ is exactly the issue. The Ethanol is aggressively hygroscopic

While it doesn’t seem like much, E10 gas can easily contain 0.5% water, but even that seemingly little bit means if you have an 80 gallon fuel tank it will contain 48 ounces of water.

That water not only contains zero energy value but will be distributed through the gas. No engine has sensors to detect and account for water, the result is the sensors picking up the excess oxygen released when water is sprayed into a cylinder that’s at 4,000++ degrees then adjust the timing based on false readings.

The real world end result is much lower fuel economy than what the greenies and politicians would have you believe.

The end result, in my case, proven over many thousands of miles, is that the cost per mile is slightly lower (about $0.03 / mile) burning ethanol-free premium fuel instead of E10.

Your math is off. At one half of one percent you will have 6.4 ounces of water in 80 gallons.

MDKMDK wrote:

Son of Norway wrote:
I buy pure (no ethanol) gasoline that I keep on hand in a couple of 5-gallon cans for snow blowers, lawn mowers, power washers, portable generators etc. The STABIL products that I buy indicate their use for alcohol-blended fuels. Are there any fuel preservatives specifically for pure gasoline and which one would you recommend? Thanks for your help.

Agree with Old Wizard - unless you go through a 5 gallon can once every decade, I probably wouldn't worry about it going bad. Even stored for that length of time it will probably still work.
Honestly, I tried fuel stabilizer about 10 years ago, and there was no noticeable difference in the fuel quality that I put it in, versus the last 10 years of not bothering. I've left ethanol laced, and pure dino, gas in my shed over the winter and it still works, when I use it next year in the mower/tractor.
Some believe that some engines might prefer you use it all up, to dry, before long term storage. However, I've never done that either, and had no problems.

Same here. I use 10% ethanol regular pump gas and no stabilizers, and I never have an issue. Been doing it this way for many years.
Every piece of power equipment produced in the last 10-15 years is ethanol ready.

When it comes to lawn mowers, string trimmers, power washers, etc. there is no advantage to premium fuel, non ethanol gas, or stabilizers, in my experience.