Engine and Transmission Tech

i have been mowing the lawn for an older guy over the summer because he hurt his leg and couldn't do it. so i went in the other day and he tells me that there is ethanol in gas witch i knew but he then tells me the ethanol will eat the rings and carbrator in small engines and old cars detoring them to the point of being rebuilt i have never herd of this is it true

Ethanol is incompatible with some plastics. Newer fuel system parts should be fine with ten or even fifteen percent ethanol blends. Some older carburetor floats and some fuel pump components might be damaged. Piston rings won't be effected; at least not directly.

Another issue is that ethanol alters the vapor pressure of fuel, which can make carbs misbehave. When I started using ethanol blended fuel, I witnessed fuel percolation problems at idle if my engine was hot. Lowering float height just a little fixed that. Now, with fuel injection, I won't ever worry about it again.

Older guys tend to resent change, especially if they don't understand the rationale behind it. Change is rarely all bad. IMHO, ethanol that's used for oxygenating winter-time fuel in urban markets is a very good thing, but mandating corn-based ethanol for year round use is lousy public policy because it doesn't make economic or environmental sense.

Curtis is right on the mark with the compatibility problems.
Carbs with plastic or foam floats will likely need to be updated.
And older plastic fittings and rubber lines should be changed out.
The ring problem stems from Ethanol's cleaning abilities.
An older engine with worn out components will stumble along just fine on regular fuel.
But add Ethanol and it cleans out all the old carbon that was propping the rings up and the engine now shows it's true colours.
The engine already needed a rebuild, the Ethanol just confirmed it.
One other caution is that Ethanol alters the fuel mix on vehicles that do not use a compensation mechanism. IE an o2 sensor.
So you will need to adjust your fuel mix to compensate.
For the racers in the crowd.
Ethanol contains less BTU's than gasoline. So you have to run a richer mixture to get your power back.(not really that simple but....)
If done right however, it lowers combustion and intake temps which lets you pump up the compression and get more power.
If you are storing a vehicle or small engine you will need to use a fuel stabilizer. Fill the tank as full as possible to lessen condensation.
And run the carb dry as Ethanol will pull moisture out of the air.
Causing you to utter bad words next spring.
Cheers
Fred

ok thanks

I try not to run it. It's diluted gasoline, which equals less miles to the gallon. A buddy of mine used to run it on a drag car. He upped the compression to 14:1. Completely flushed the fuel system at the end of the day.

So far, 3 of 3 ATVs I have repeatedly had to clean the carbs for have been symptom free since I scolded the owners that if they don't run pure gas I will not repair them again, they all are praising me on how they all fire right up even after sitting for two months. Puregas.org I believe it is shows a nationwide list of filling stations you can get ethanol free fuel.

In my small engines I use and ethanol stabilizer and run them completely dry before storing them.

Tim

In newer small gas engines, the best advise is "Avoid when possible."

For older gas engines, especially smaller, "Do not use" should be considered gospel.

Plenty of reasons behind this. As already mentioned, it can ruin rings and overheat cylinders.

Another good one is that Ethanol sucks up moisture AND starts to go stale after 90 days! Standard non-oxy fuel takes longer than this to spoil.

-BMC.

I have to drive 60 miles to get real gas. No one sells it in Asheville anymore.

Tim

lucky for me its only 10 miles to get some "real gas" tim