water in gas

[cheyenne]

I just heard on the news that the new ethanol gas absorbs moisture and is rusting out small engines. Anybody had a problem with thier saws....Cheyenne

[Larry]

My small engine dealer along with my outboard motor shop have warned me about gas problems...they have engines coming in daily for repair.  The big problem seems to be gum in the carb.

For my chainsaws I'm only mixing a gallon at a time...if it sits for a month I dump it.  For my big outboard I add Sea Foam.  For the small outboard, and generator I use STA-BIL.  Lawnmower and power washer get fresh gas and drained over winter.

[John Mc]

The ethanol in gas will combine with moisture in the air. when that happens, the ethanol/water mix drops to the bottom of the tank. That mix is corrosive. It's also a problem since part of where the fuel blend gets it's octane rating is from the ethanol. When the ethanol drops out, what's left is significantly lower octane. burning that remaining gas can do a real number on your engine. Lastly, if you are humming along at full throttle and happen to suck a slug of ethanol/water mix into the engine, you are running something with no lubrication (the oil in your oil/gas mix will also float on top of the ethanol).

Best thing is to not burn ethanol, if you can find an alternative. Fortunately for me, there are a couple of stations near me that sell ethanol-free gas. If you can't get ethanol free gas, then you need to be even more careful about not burning old gas. Use it before it has time to suck moisture out of the air. Keep storage tanks tightly capped (so it's not being constantly exposed to new air). And don't leave it lying around in your saw's tank for extended periods.

John Mc

[cheyenne]

Maybe this is just another way for the government to stimulate the economy by making us buy new engines that are made in China.....Cheyenne

[Bill]

. . .

Best thing is to not burn ethanol, if you can find an alternative. Fortunately for me, there are a couple of stations near me that sell ethanol-free gas.

. . .

John Mc

Seems I recall something in another post ( or maybe a boating site ? ) about getting ethanol free gas from the local small plane airport . Cost is high but small planes definitely can't have any absorbed water freezing while in the clouds  . Downside ( for some ? ) , besides the cost,  maybe that some or all av gas still may have lead.

[pineywoods]

Ethanol free gas.....Use avgas, the feds control the standards for avgas, not state or local.
Alcohol is an absolute no-no for 2 reasons..It corodes the heck out of aluminum tanks and fuel lines, and then there's the water problem. Real avgas is 100 octane and does contain a small amount of lead.  Might cause a litltle lead fouling of the spark plug. Some small airports may sell car gas for use in  older piston-engined aircraft, it will not contain alcohol but may be 83 octane.  Yes it can be legal to do that. Most older aircraft engines were designed to run on 80 octane lead-free fuel and they generally don't like the lead in 100 octane.

[John Mc]

Avgas has a LOT of lead, not a bit. About 3 times or more the amount of lead that used to be in leaded auto gas. It's called 100LL Avgas (100 octane, Low Lead) only because it's got less lead in it than the old 100 Avgas, but that "less" is still a lot more than you ever saw in your car gas.

The old "80 octane avgas" was also leaded, but had far less than the 100 octane stuff. It was NOT actually the same as 80 octane when measured the same way as car gas is. When measured by auto gas methods, it's higher than 80 octane. Typically, older aircraft (particularly those with smaller engines) designed to run on 80 Avgas, can run regular unleaded auto gas. These engines often have problems with fouling from all the lead in the 100LL Avgas

Some airports, particularly smaller will stock auto gas for use in these aircraft. If they do, it will almost certainly be ethanol-free. As Pineywoods noted alcohol is a definite no-no in aircraft. I believe prohibited by the FAA. I'm a pilot and keep on top of these things. My aircraft can burn premium autogas, but only if it has no ethanol.

One of my local sources of ethanol-free gas is a small grass strip airport near where I live. He charges more than the gas station, but it's cheaper than driving to the next town to buy gas from one o the stations there that has ethanol-free gas.

[timber tramp]

http://www.stihlusa.com/faq.html

   Stihl USA says that their engines are fine to run ethanol up to 10%.

[tractorhal]

I haven't tried this, but was told by a weigts&measure person that you take 3gals. of gas, a cup of water and put a food coloring  in, mix up, then pour it in the gas container, shake  well, let sit for 5-8 minutes, then shake again, let sit 5-8 mins. again, then pour gas into another container until you start to see the water/food coloring and stop. The gas has no ethanol. It was absorbed into the water. when I try this I think I will us a clear container and siphon the water out of the bottom then put the gas in an approved container and mix.   

[timber tramp]

Curios, please keep us posted.

[ely]

our local country store has gas that is ethanol free, according to them. but who really knows. i do buy my saw gas and mill gas there. my truck i could care less about. i burn anything in there from a mixture of gas and diesel, chainsaw fuel that gets too old for saws,and the ethanol gas that i buy at other stores.

[John Mc]

I haven't tried this, but was told by a weigts&measure person that you take 3gals. of gas, a cup of water and put a food coloring  in, mix up, then pour it in the gas container, shake  well, let sit for 5-8 minutes, then shake again, let sit 5-8 mins. again, then pour gas into another container until you start to see the water/food coloring and stop. The gas has no ethanol. It was absorbed into the water. when I try this I think I will us a clear container and siphon the water out of the bottom then put the gas in an approved container and mix.   

That will get most of the ethanol out of the gas. However, you will be left with rather low octane gas (possibly less than the octane for regular gas, even if you start with premium). As I've mentioned on here a couple of times: the ethanol in the mix is part of where that gas gets its octane rating. Unless you have some way of testing the octane, or boosting it, you risk doing damage to your engine. You may be better of just running gas with ethanol in it that is fresh, was bought from a station with a decent turnover, and was freshly mixed with 2 cycle oil. Don't let it sit around and suck up moisture from the air, don't store the leftover stuff in your chainsaw tank, and dump any left over mix into your car's gas tank if it's getting old.

John Mc

[John Mc]

our local country store has gas that is ethanol free, according to them. but who really knows.

To check for ethanol in gas:

1 find a clear plastic or glass bottle (a 1 liter plastic coke bottle works)
2 put some water in - (1/4 full or less)
3 Mark the level of the water on the bottle
4 Add gas till almost full (leave some air space for shaking)
   the gas will float on top of the water
5 cap and shake the bottle well
6 let it settle

After settling, you'll see the gas floating on top again, and the "water" on the bottom. If the water is higher than the mark you put on the bottle, then you have ethanol in your gas. The water combined with the ethanol and settled out. (A tall thin bottle is easier than a short fat one... the taller and thinner, the more of a difference you can see in the before and after heights of the water. That's the reason for a coke bottle, rather than a peanut butter jar.)

If you want to get fancy, you can actually get a pretty good read on what percent of ethanol you have. Instead of the coke bottle, use a graduated cylinder or test tube (like a chemist uses), with volume markings on the side. Put 10 cc water in the cylinder, add 100cc gas. After the shaking and settling, read how high the water/alcohol mix now is, and subtract the original amount of water. What's left above that original amount is the % of alcohol.

Example: 10cc water, 100cc gas.
after shaking and settling you see 15cc water-ethanol mix.
subtract the 10cc water you started with: 15-10=5
You have 5% ethanol

It's not completely accurate, since some of the ethanol may still be mixed in the gas. It should be pretty close, though, especially if you gave it a good shake and let it settle long enough. If all you want to know is "does it have ethanol or not", all the measuring is overkill.

[John Mc]

I haven't tried this, but was told by a weigts&measure person that you take 3gals. of gas, a cup of water and put a food coloring  in, mix up, then pour it in the gas container, shake  well, let sit for 5-8 minutes, then shake again, let sit 5-8 mins. again, then pour gas into another container until you start to see the water/food coloring and stop. The gas has no ethanol. It was absorbed into the water. when I try this I think I will us a clear container and siphon the water out of the bottom then put the gas in an approved container and mix.   

another thought on this:

100LL aviation gas is dyed blue. We check the tanks before each flight by draining a sample from the low point. If there is water in the gas, it shows up as a clear "bubble" that sinks to the bottom of the sample jar. The gas stays blue and floats on top. I'm not sure how the dye in that gas compares to the food coloring you mentioned, but I'd check to see which thing gets dyed, the water or the gas-ethanol mix (or both?) before you start pouring it off.

[Polly]

           my brother used to work on chain saws especially sthl his advice to me was dont leave gas in the saw longer then overnite start engine up drain tank and let run till it quits that way the carb will not gum up my openion saws run better using fresh medium grade gas just a thought  8) 8)