What effect does Ethanol have on small 2 cycle engines?

Status
Not open for further replies.
Joined
Nov 17, 2004
Messages
151
Location
Kansas, land of OZ
I know that this is a Oil forum, however I was wondering what the effects of Ethanol/Gas mix would be on small two-cycle engines because of the fact that they lubricate with oil in the fuel. In the not too distant future I think that we may not be able to get stright unleaded fuel and it may well be a much richer mix than 10 percent ethanol and I'm concerned that small two-cycle engines may have problems with that. Most of the owners manuals that I've read say no more than 10% ethanol if they allow any at all. I remember when lead was taken out of gasoline and everyone was sure their engines would die a quick death. Just wondering if anyone else had that thought.
rolleyes.gif
 
2 stroke engines have no problems using alternative fuels. I believe the radio controlled 2 strokes generally run on a nitro-methanol/oil mix.

However the oil/fuel mixture may not stay mixed with certain blends. That could be a problem.

I tried using gasohol in my dirt bike years ago. The oil remained in suspension without trouble. However the alcohol disolved the plastic gas cap! It was actually kinda funny.

As long as the oil remains in suspension I would not expect problems.

Chris
 
Increasing the alcohol content in a gasoline mixture will have the effect of leaning the mixture out proportional to the amount of alcohol added. For example using pure alcohol in place of the gasoline would result in having to set the carb jetting for roughly twice the fuel volume as pure gasoline would require in addition to the required amount of oil of course. This is based on the fact that alcohols have roughly half the energy per volume as gasoline does. Another thing to consider is that gasoline power drops fairly sharply on either side of stiochromic; wheras alcohol power falls off very gracefully for over rich mixtures and melts expensive things in a hurry with lean mixtures. So if you are going to play with alcohol start rich to avoid melted pistons etc. Rickey.
 
The gasoline molecule does not have an oxygen molecule. Oxygenated fuels like those that contain ethanol tend to attract water. With that in mind, just simple well known practices like always using fresh fuel and basic maintenance should negate this problem.

California, and other parts of the country have been using oxygenated fuels for about the last fifteen years. The fears of what would happen in autos that were never designed to used this blend never really materialised, thankfully.
 
New cars are only requires to exept 10% ethanol so other than the E85 alternatives stations and vehicles specifically built to run that carp I don't think you will see over 10% any time soon. The real problem with alcohol in this sort of application is as mentioned the fact it attracts water.
 
quote:

Originally posted by Cujet:
2 stroke engines have no problems using alternative fuels. I believe the radio controlled 2 strokes generally run on a nitro-methanol/oil mix.

The radio controlled models use a glo-plug rather than a spark plug. this is why they use the nitromethanol fuels.
 
My point was that there are 2 stroke engines running just fine on alcohol based fuels.

As previously mentioned, jetting tends to be different for alcohol. Along with the water absorbtion issue.

For lawn eqpt you can probably adjust the screw.

Chris
 
We have a Snow blower that comes with a Junk Tecumseh 2 stroke engine. The manual saids do not use Gasohol. My dad been using gasohol since 1998 and the engine does fine.
 
From my understanding......ethenol eats away at the 2-Cycle oil and as such should be used up quickly. You don't want to leave it sitting around for a month or so.
Other than that you can mix it and use it. Just don't store it for long.
 
most small engines state it is OK to use gas that contains up to 10% ethanol and they state this right in the owners manual. if in doubt check the manual. just dont go out and use any e85.

also, all certified modern 2 stroke oils that you can buy off the shelf at lowes or home depot are designed to be compatible with 10% blends.

i cant confirm compatibility of expensive botique oils.
 
I have older commercial Echo 2 strokes in my weed-eater and back-pack blowers. Both had to be richened-up on both high and low speed jets last spring when ethanol fuels came along. Ran really bad on these ethanol blended products with reduced top speed, rougher running and popping, and alot less power.
 
quote:

Originally posted by Don Stefanik:
From my understanding......ethenol eats away at the 2-Cycle oil and as such should be used up quickly. You don't want to leave it sitting around for a month or so.
Other than that you can mix it and use it. Just don't store it for long.


I agree that you want to use ethanol up quickly (30-60 days max), but not for the reason you stated. Ethanol doesn't "eat" away the oil, it attracts moisture. The fuel will absorb moisture and turn to **** over a period of time. This is really evident in small carbs that sit over a long period of time with ethanol in them. It is fine to use as long as it is fresh.
All fuel in MN in mandated to have ethanol in it except for special pumps that are supposed to be used for Classic cars, small engines, and offroad vehicles. I always makes sure that the last couple tanks of fuel are non-ethanol mixed with Seafoam before storing for the season. Since I have followed this method, I never have a problem with gummed up carbs after storage.
 
Status
Not open for further replies.
Back
Top