Non ethanol fuel question

[TobyU]

I have never used ethanol blended fuel, so some of my commentary is speculative.

• Agree with purchasing any fuel from a high volume/turn over supplier.
• Also only purchasing sufficient fuel for your relativly short term needs (whatever they may be)

Storage of petrol:

Most, if not all, petrol will store for at least 6 months plus, with negligible deterioration. To achieve this, the container must be gas/air tight and filled to 75% capacity or more. If these two factors are met, then the storage temperature has little bearing on its keeping quality.

As has been pointed out by others - Most fuel tanks are open to atmosphere:

• This means that air can enter/exit. Air contains moisture (% will vary according to prevailing condition). Warm air contains more moisture than cold. When warm moist air enters the tank, the moisture will condense, on cold inner walls of the tank, forming free water (droplets), . These droplets will fall to & collect at the bottom of the tank. Petrol with ethanol may absorb some of this water - this is okay as it will have little effect on the combustion process. However the free water at the bottom of the tank may may # rust the tank bottom or # enter the fuel delivery/metering system and cause engine running issues. The solution is to regularly drain the tank sump (if fitted) any water traps and the carburettor float bowl thus removing free water.
• Also means any tendency of the fuel (petrol) to loose volatile components, causing a reduction in fuel quality. Filling the tank (minimising air space) will slow the process, as will mixing in fuel "inhibitors" however for long term storage it may be best to empty the whole fuel system. NOTE: In most short term storage situations, adding fresh fuel to old, will restore most of the fuels performance.

You hit the nail on the head when you talked about long-term storage and the fact that most people don't have these best conditions.
We all hate these newer and the vast variety of these EPA nozzles but the only thing they do better is they keep the can airtight and keep the gas fresher longer.
It doesn't make things perfect or all warm and fuzzy but it certainly helps.

Most people have a gas can that the top is pretty much wide open and they pay no attention to when they get gas and when that gas can is getting down to the last couple of inches, especially in a 5 gallon can, and they're going out to mulch leaves for the last time of the year....they just pour that old stale stuff right into their mower and sometimes they tip it all the way up and get all the grass particles and dirt and everything else and even water that's been sitting at the bottom from that gas can right into their lawn mower tank.
They mow because it runs just fine that day...but come back in a week and especially come back the next March or April and that mower doesn't stand a chance of running.

 

[Hammermechanicman]

Just my personal experience.
I have kept 87 E10 gas in sealed gas cans for over a year with no problem.
The 1989 motor home with 454 carb engine sat for 5 years in the barn and started and ran fine. E10 87 gas with no stabilizer or other fuel treatment. Now gets used once a year to take the grandkids camping. Starts fine.
I use regular 87 E10 in about 20 pieces of equipment without issue. I have 7 5 gallon gas cans I fill a few times a year for equipment. As long as I keep then SEALED I have no issues. I fill them in the fall for the generator and if no power failures use the gas in the spring. Never have a problem.

 

[7394]

 

[Skippydiesel]

Just my personal experience.
I have kept 87 E10 gas in sealed gas cans for over a year with no problem.
The 1989 motor home with 454 carb engine sat for 5 years in the barn and started and ran fine. E10 87 gas with no stabilizer or other fuel treatment. Now gets used once a year to take the grandkids camping. Starts fine.
I use regular 87 E10 in about 20 pieces of equipment without issue. I have 7 5 gallon gas cans I fill a few times a year for equipment. As long as I keep then SEALED I have no issues. I fill them in the fall for the generator and if no power failures use the gas in the spring. Never have a problem.

That's great my friend, however I would suggest that you drain the tank sump and any in line water traps, at least once per year.

 

[bertsmobile1]

So I guess my original post had some validity but my concern still is as follows;
If the available ethanol free fuel is 91 octane, is it safe to use that or should I mix a little normal fuel (10% ethanol) to dilute the octane rating?

Another point of interest is that since most service stations have 4 different grades of gas with a common hose and nozzle, whenever we make a selection to pump gas, we are going to first receive the fuel that’s in the hose from the last user. The valve to that controls the flow is in the pump, not all the way back to the tank.

I realize it’s only a small amount of fuel, however if you were filling a 1 or 2.5 gallon container, it would be a significant percentage.
One way around this would be to first pump of your fuel of choice into your vehicle so that you get 100 percent of your desired fuel for your mowers or small engines.

High octane is necessary in high compression engines
Mower engines are pretty low compression & low reving as well
They would be happy running power kerosene once the manifold got hot enough to vapourise the kerro.
There is a massive amount of ignorant B S spread by the ignorant &/or illinformed who read some thing that applies to NASCAR engines or formula 1 open wheeler engines then blindly apply it to mower engines because they do not understand the difference between an engine that runs 12:1 compression @ 12,000 rpm to one that runs 8:1 compression at 3,600 rpm.

 

[bertsmobile1]

The only harm ”from” ethanol is that it carries water in solution, then carries that water into the carburetor. If allowed to sit it will do nasty things. No additive or treatment does any good.

Small engines have ventilated gas tanks, open to the atmosphere, open to collecting moisture. Automobiles have sealed gas tanks with very little outside air axchange.

Err if no air gets in how does the fuel get out ?
All tanks are vented some where

 

[Timbuktu]

As far as ethanol, I was always under the impression that it was not good for small engines. If so, maybe this is outdated information. I personally don't use ethanol in anything I own, small motors or vehicles.

 

[TobyU]

High octane is necessary in high compression engines
Mower engines are pretty low compression & low reving as well
They would be happy running power kerosene once the manifold got hot enough to vapourise the kerro.
There is a massive amount of ignorant B S spread by the ignorant &/or illinformed who read some thing that applies to NASCAR engines or formula 1 open wheeler engines then blindly apply it to mower engines because they do not understand the difference between an engine that runs 12:1 compression @ 12,000 rpm to one that runs 8:1 compression at 3,600 rpm.

Yep.
More like barely over 7 to 1 compression ratio and 2900 RPMs for most things today. Lol
You are so right though. People read something on the Internet and if it's conveyed to them in just a certain way they accept it as the gospel truth. SMH

There's also a lot of information over the past few years that has kind of been changed and rewritten which makes things even worse.
It's not that they're actually lying but they're not giving a complete picture of everything or even the options one is likely to encounter.
They, certain people, groups, companies etc are literally trying to shape the world by what information they promote.
Unfortunately they are doing this to a pretty good point.

 

[TobyU]

As far as ethanol, I was always under the impression that it was not good for small engines. If so, maybe this is outdated information. I personally don't use ethanol in anything I own, small motors or vehicles.

It's just not that big of a deal.
I don't think I have used any gas that was ethanol free since 1998 or so.
Everything in my area has been 10% ethanol since then.
Prior to that even Meijer department store gas station had three grades and two of the three were ethanol free from what I remember.
Back in the day it was Speedway that came on strong and all of their fuel had 10% ethanol. They also used to be cheaper than everyone else and we used to say all the time "I'm not buying that cheap crap gas!" because for only 3 or 4 cents more at other stations we could get ethanol free.
But that all changed in just a few short years.

 

[TonyPrin]

High octane is necessary in high compression engines
Mower engines are pretty low compression & low reving as well
They would be happy running power kerosene once the manifold got hot enough to vapourise the kerro.
There is a massive amount of ignorant B S spread by the ignorant &/or illinformed who read some thing that applies to NASCAR engines or formula 1 open wheeler engines then blindly apply it to mower engines because they do not understand the difference between an engine that runs 12:1 compression @ 12,000 rpm to one that runs 8:1 compression at 3,600 rpm.

Here's the reality of all this in a nutshell:

• The consensus is there is no meaningful detriment (if any) in using high octane fuel in small engines. (Not my opinion but most aren't with me.)
• No one is suggesting a high octane benefit in small engines. There is a price detriment to high octane which makes it less desirable unless a trade-ff exists.
• E10 gasoline has a potential issue from phase separation, mitigated by prudent and short-term storage practices. Many don't see it as a meaningful concern.