Chemistry Question

[HuskStihl]

For anyone with a chemistry background, even those of you who just run a meth lab out of your bathroom, here's a question. If I take some fresh 93 octane premium (which will contain ethanol), mix it with the appropriate amount of Stabil, and stihl or husky oil, then immediately put it into one of my 8 TruFuel cans and seal it, how long will it last?
Thanks

 

[stihl023/5]

Well I have fuel with startron in the lawn mowers from last year and they start after the snow melts. That is about 6 months.

 

[wcorey]

It's a complicated question with lots of variables that doesn't lend itself to a straight forward answer... Not from me anyway.

A good, ethanol specific fuel stabilizer (combined with the sealed container) will help prevent absorption of water and it's subsequent emulsifying with the 2-stroke mix but there's still the issue of octane degradation over time.
A lawn mower is generally pretty low compression and will tolerate all sorts of sub-par fuel, a chainsaw tends to be in a 'higher state of tune' and more prone to detonation so will suffer consequences not seen by a typical mower. A motor blowing 210 psi with advanced timing is a very different animal from one stock at 140 psi or even strato versus non...
I hear numbers bandied about like 3-6 months (so many octane points per month) but that's just semi meaningless generalities without including a bunch of other info.

I mowed my lawn all last year on old nasty gas dumped out of the saws I bought.

So..., it depends on the individual saw, the fuel, the mix, the stabilizer, the amount of time...


Bill

 

[taxidermist]

I have a fuel test in my shop in mason jars 1 yo right now.

Air tight with startron= like the day i did it

Vented with startron=almost all evaporated with phase seperation

vented with no startron= lots of phase seperation with more evaporated then the last.

Now I have to get back to my meth.......

Rob

 

[nmurph]

I have a fuel test in my shop in mason jars 1 yo right now.

Air tight with startron= like the day i did it

Vented with startron=almost all evaporated with phase seperation

vented with no startron= lots of phase seperation with more evaporated then the last.

Now I have to get back to my meth.......

Rob

You missed the control: air tight with no additives.

 

[Guido Salvage]

You missed the control: air tight with no additives.

He used it to cook the meth.

 

[machinisttx]

No idea, but I'm running 89 octane with ethanol bought 6+ months ago through everything I have and don't have problems. No stabilizers added, stored in plastic gas cans. My riding mower fired right up, still half full of fuel purchased about the same time. *shrug*

 

[ChainLightning]

For anyone with a chemistry background, even those of you who just run a meth lab out of your bathroom, here's a question. If I take some fresh 93 octane premium (which will contain ethanol), mix it with the appropriate amount of Stabil, and stihl or husky oil, then immediately put it into one of my 8 TruFuel cans and seal it, how long will it last?
Thanks

For your information I run my meth lab out of my bedroom.

 

[HuskStihl]

For your information I run my meth lab out of my bedroom.

Impressive!

 

[ChainLightning]

Impressive!

Thanks. I try to be a little bit more clean then making it in the bathroom.

 

[w8ye]

I use Pennzoil Air Cooled 2 stroke oil at 30:1 mixed with regular gasoline bought at the nearest discount gas station.

I've run a couple chainsaws this week that had old gas in them

Dolmar 6800iH - gas mix was at least a year old in the chainsaw tank, maybe much longer? The last time I had run the chainsaw was last summer. Started first pull. The old "i" model Dolmars will start with the choke on.

Ran a Dolmar 7900 and its gasoline mix had been in the chainsaw tank for two years. I had not used that 7900 in two years and it had about 3/4 tank. Started right up. About three pulls with the choke on and two with it off.

They both ran fine.

I have not had any trouble with bad gasoline around here.

But I have purchased old used chainsaws that I dumped the gas mix in the gravel driveway to kill the weeds. Also had gasoline several years old that I ran in the lawn mower to get rid of it.

I also remember finding mud, or whatever, in the carburetor 40 years ago

 

[ChainLightning]

I use Pennzoil Air Cooled 2 stroke oil at 30:1 mixed with regular gasoline bought at the nearest discount gas station.

I've run a couple chainsaws this week that had old gas in them

Dolmar 6800iH - gas mix was at least a year old in the chainsaw tank, maybe much longer? The last time I had run the chainsaw was last summer. Started first pull. The old "i" model Dolmars will start with the choke on.

Ran a Dolmar 7900 and its gasoline mix had been in the chainsaw tank for two years. I had not used that 7900 in two years and it had about 3/4 tank. Started right up. About three pulls with the choke on and two with it off.

They both ran fine.

I have not had any trouble with bad gasoline around here.

But I have purchased old used chainsaws that I dumped the gas mix in the gravel driveway to kill the weeds. Also had gasoline several years old that I ran in the lawn mower to get rid of it.

I also remember finding mud, or whatever, in the carburetor 40 years ago

wow 30:1? Not too many people run em at that anymore. I use that Penzoil oil too.. good stuff. That is if I don' have anymore of the Husky blend oil left.

 

[mad murdock]

I use valvetec ethanol eliminator and I run all my saws at 32:1 premix. No issues yet. Every now and the. I get a few gallons of non ethanol premium and mix it up, so far so good. No meth here just airplane dope (and fabric).

 

[Bill G]

It's a complicated question with lots of variables ..................

Bill

The question is neither complicated nor does it contain any variable. If the container is air tight then no reaction will occur with the absence of O2

 

[wcorey]

If the container is air tight then no reaction will occur with the absence of O2

Well, this is true, though the majority of octane loss is typically due to the lighter volatiles (responsible for octane level) evaporating faster than the heavy ones.
Yes, this is still mitigated by a well sealed container.

Oxidization accounts for only a small percentage of loss but can the oxygenates that are already additives in the fuel cause continuing oxidization even in a sealed container?

From what I'm reading, some degree of octane degradation occurs with age regardless of the storage conditions, though it can be slowed down significantly with proper care.
Why I don't know and I can't find any numbers indicating specifically how long or how much.

Might not be a big deal, but I've yet to see a straight answer on this from a source I'd trust.

Fuel threads can be a lot like oil threads, lol.



Bill

 

[ROWDY]

Loss of octane in a fuel has never been a major issue in my experience. Its when ethanol becomes an acid that destroys a fuel management system. (gaskets, seals, O rings as an example) My second issue would be, less lubricant than 100% petroleum. Also note, other additives that fuel distributers add for the winter months.

 

[ChainLightning]

I use valvetec ethanol eliminator and I run all my saws at 32:1 premix. No issues yet. Every now and the. I get a few gallons of non ethanol premium and mix it up, so far so good. No meth here just airplane dope (and fabric).

Ethanol eliminator ehh? Where would I have to go to get that stuff?

 

[w8ye]

Here it is . . .

ValvTect - ValvTect Ethanol Gasoline Treatment

 

[stihl023/5]

This works well also.

View attachment 288909

 

[nmurph]

How does it eliminate ethanol? It sounds like snake oil to me.