Ethanol and 2 Stroke Lubrication Issues

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I have been reading somewhere that the Ethanol in gas is causeing lubrication problems in 2 stroke engines. The theory being that the alcohol strips the oil off the cylinder walls. I can see it modifying surface tension but I can't see how it would strip the oil off the cylinder walls. Oil is soluble in gasoline and alcohol so what is the difference?

Perry
 
Here is some interesting reading on alcohol fuels:

http://en.wikipedia.org/wiki/Alcohol_fuel



I'd be interested to know for sure what percentage of ethanol is required to have negative effects on two cycle lubrication. Some two cycle engine manuals do make reference to not using fuel with more than 15% ethanol. That might possibly be the threshold. At existing levels, I've not experienced any negative effects in any of my numerous two cycle engines.

I'd be more concerned with the effects ethanol will have on seals and other rubber/synthetic components.
 
I can't testify to the wear issues but the corrosion issues have caused problems in my engines. Motorcycles especially don't like it. They have too many disimilar metals to corrode. I have had problems with my Stihl 2 strokes. The Alcohol desolves the adhesive that is used to seal the welch plugs in the carburetors. It desolves it and it forms a gel that glogs the jets and they won't run at that point. Maybe glogged jets from corrosion and desolved polymers is causing a lean condition which leads to lubrication failure.

Perry
 
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As long as I can still get it, I will continue to use non-ethanol gasoline.

Even then, I run a little Seafoam through my motorcycle, atvs and lawnmowers.
 
We have about a half dozen Stihl products at my workplace and have not suffered any noticeable ill effects from E-10 (Knock furiously on wood). Some of our stuff even sits for a month or three with fuel in it....I'm trying to eliminate this practice.

Boraticus, here is an article from a guy that runs a top notch chainsaw safety company. His e-book is outstanding and worth every penny (very reasonable price, IMO). BUT...in supporting his company, he does sell stuff and promote his supporting companies. Yes, he sells and promotes that "canned 2 cycle gas" stuff. So, his argument is obviously biased as evidenced by the shameless plug at his article's end for the use of "pure" 2 cycle pre canned fuel (outrageously priced).

But, there might be a few tidbits of truth hidden in his views. Take it for what it's worth. Again, I haven't had the problems others speak of...yet.

Here's his article: http://www.forestapps.com/articles/two_cycle_fuel.html

Just trying to share info for intelligent discussion/disection. In one of his recent e mail "notes", I think he implied that the switch to e15 might cross the threshold of 2 cycle carbs, but I didn't save it and can't remember. He's big on the idea that ethanol molecules are bigger and more difficult to pass thru the jets and can result in lean conditions.

Edit: here's his other article: http://www.forestapps.com/articles/Fueledbyethanol.htm that states:"Alcohol in the fuel requires more flow to maintain power needs. In two cycle engines the fuel flow can also relate to lubrication needs. It takes a more open, counter-clockwise adjustment on the screws, to allow enough fuel to run properly. Most carburetors will adjust 10% to 12% but will not accept any higher percentages very well. You should try to a locate a gas supply without ethanol if at all possible."

Don't know if I can trust his info based on his writing (pitching style).
 
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"He's big on the idea that ethanol molecules are bigger and more difficult to pass thru the jets and can result in lean conditions."

Not to be rude, but the above statement is right off the wall.

An ethanol molecule is .44 nm. One nm. (nonometer) is one - one millionth of a millimeter. An ethanol molecule is less than half that size.

Say a jet has the same diameter as a human hair (probably much wider). A human hair is between 50000 to 80000 nm. in diameter. Accordingly, more than 100K to 160K ethanol molecules abreast could march through a jet the width of a human hair.

Sorry. Can't buy that theory.

I read the piece you linked. Didn't see anything that would cause me to change my present methods of buying/handling two cycle fuel. Which is pretty much minimal.

I buy/use pump gas with ethanol in it, mix it as per manufacturer's instructions or a little richer with a good quality conventional two cycle engine oil.

I often leave outboard motor fuel mixed and sitting over winter for five to six months. Put the fuel tank on the engine in the spring and go fishing. Been doing it for decades. Never had a problem other than water in the fuel once. The water was in the fuel when I bought it. Other than that, no issues with two cycle fuel in any machine regardless of mix ratio or length of time left mixed and unused.

It may be of some importance to recognize that in this part of the country, winter is very cold. I suspect that cool temperatures and the fact that the fuel is kept in an air tight, sealed containers, fuel degradation will be minimal if at all.

I certainly don't worry about fuel deterioration. Not in this part of the world.
 
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Not to be rude, but the above statement is right off the wall.


I don't consider an honest opinion to be rude (whether you were talking to me, or him!). I value your confident opinions here.

In his defense, he was talking about making the carburator needle adjustments bigger....not talking about jets. A mistake on my part, as I know/thought jets to be fixed in size.

But either way, I imagine you don't buy his theory. I just threw it out for comment. As mentioned, I saw some red flags right off.

I'm glad my "less than perfect" ways with e-10 2 cycle fuel use/storage meets with your methodology. I'm waiting for it to bite me in the hind end, but maybe it never will.

Thanks and take care.
 
Sounds more like he's saying the right thing, but for the wrong reasons.

Ethanol has less energy per unit volume than gasoline (66%), or in other words, an oz of gasoline produces more energy than an oz of ethanol.

This doesn't have anything to do with the molecule size, but instead with the chemical makeup of the two fuels.

What that guy is trying to say is that to get the same power, you have to feed it more E10, which is technically right. In real world terms, you're talking about a pretty small amount- we'd need to up the jets by 3.5% to account for that little it of less power per unit volume in that 10% of the gasoline.

I suspect that most 2 cycle engines already run rich enough anyway to make that a moot point.
 
Snake oil salesmen need to create a necessity for their products. Generally, that necessity is "the seed of doubt" sewn in a customer's mind.

Despite the fact that people aren't having problems, they are led to believe that they've just been lucky so far. Accordingly, they buy the product to calm their newly created fears. As time goes by and the problems that they didn't have continue to be non-existent, they believe that the snake oil did it's trick. The fact that they probably paid big bucks for it, reinforces their belief.

Fortunately, for most of us, we can see through the smoke and mirrors and make sound, sensible purchasing decisions which over a lifetime, will save us a great deal of money.
 
+1.

Corrosion, fuel line and diaphram damage are the big worries of ethanol in 2 cycle power equipment. The hindrence of lubrication is not something I have heard before. Interesting.
 
No, E10 doesn't effect 2 stroke engines. We have had E10 here in Illinois for years, and 2 stroke engines last as long as ever.
 
There are some very good additives available on the market to help alleviate some of the problems that many users have found when using ethanol in two-cycles.

One is AMSOIL Quick Shot.
 
Originally Posted By: tig1
No, E10 doesn't effect 2 stroke engines. We have had E10 here in Illinois for years, and 2 stroke engines last as long as ever.

+2 E10 is relatively benign in 2 strokes. My 30 year old Yamahopper says so! High performance 2 strokes (MX bikes) can and do see some fall off of throttle response if the rider is experienced enough to notice. But lubrication issues? I haven't seen or heard of any specific to eth/lubrication. There is way more risk from some of the current crop of two stroke oils available to have lubrication problems. Choose your two stroke oil carefully. It only lubes one cycle at a time, but it needs to count!
StarTron supposedly has a fuel additive to combat ethanol "issues". I think it's like boraticus stated above. Someone makes a product to address a problem that either doesn't exist, or has little potential for harm, and then makes a big deal out of it.
 
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