water in low octane gas

[gerard]

Just thought I'd share a learning experience. Sept 09 bought a good commercial grade weed whacker. Worked fine until last week when I couldn't get it started. In to the shop, regular mechanic couldn't get her started, finally fixed and they said problem was water in gas and they couldn't warranty. Thought it was bull since I store gas inside, hadn't used in the rain, and keep the container sealed up. They asked what octane I used and I told them 87, told me that was the problem. Said the cheaper gas grades can have ethanol in it which attracts water out of the air. Went home, poured out some gas into a graduated plastic cylinder and sure enough, there was a blob of water in the bottom. (Confirmed with some kolor cut paste). I guess bottom line is my small engines will now run on high test. May save some of you some aggravation!!

 

[Bird]

I was using 87 octane gas in my Stihl for awhile and never had a problem, but when I bought the little Mantis tiller, the manual specified 89 octane and the same 50:1 oil ratio as the Stihl. So I went back and looked at the manual again for the Stihl, and sure enough, it calls for 89 octane; don't know how I overlooked that before. So I'm running 89 octane and Stihl's synthetic 2-cycle oil in both engines.

 

[Duffster]

Stihl's are aproved for E10 also.

Just thought I'd share a learning experience. Sept 09 bought a good commercial grade weed whacker. Worked fine until last week when I couldn't get it started. In to the shop, regular mechanic couldn't get her started, finally fixed and they said problem was water in gas and they couldn't warranty. Thought it was bull since I store gas inside, hadn't used in the rain, and keep the container sealed up. They asked what octane I used and I told them 87, told me that was the problem. Said the cheaper gas grades can have ethanol in it which attracts water out of the air. Went home, poured out some gas into a graduated plastic cylinder and sure enough, there was a blob of water in the bottom. (Confirmed with some kolor cut paste). I guess bottom line is my small engines will now run on high test. May save some of you some aggravation!!

I have a hard time believing you have anymore water in your fuel because of the ethanol.

 

[DieselPower]

Stihl's are aproved for E10 also.



I have a hard time believing you have anymore water in your fuel because of the ethanol.

Shouldn't be to hard to believe. Simple science. Ethanol attracts water, it's hygroscopic. Your science project for the weekend is to get some gas and some alcohol. Get two glass jars and pour some gas in one and alcohol in the other. Then pour some water in each. The water sinks to the bottom of the jar with gas and completely mixes with the alcohol. Now dump some of the water/alcohol mix into the gas jar. The two will now mix together and if you add enough of it the water already in the jar will mix into solution. If left to set for a period of time a portion of the water will settle out.

 

[Bird]

Stihl's are aproved for E10 also.

The manual for my 4 year old Stihl string trimmer doesn't even mention alcohol, pro or con, in the fuel, but the Mantis is newer and the manual does approve E10.

 

[Reg]

It doesn't "attract" water, it absorbs it.
It is primarily what "Dry Gas" (& similar gas line anti-freeze) is.
They enable water to be carried into the cylinder and turned to steam in the combustion process.
Look up water injection sometime.

The O/P stated that he keeps the trimmer indoors and the gas can sealed.
Ethanol won't "attract" moisture from humid air through the sides of a can.

As to whether or not refineries and distributors feel they can relax their efforts to remove water on the basis that the additional ethanol will absorb it.... possible.
I doubt there is more ethanol in 87 vs 89 or 93 gas, though that may vary by brand name.

 

[AndyMA]

I agree that there is probably not any difference in the amount of ethonol in 87 vs 89 or 93 gas. The ethanol definitely absorbs water. Just ask boaters. They are selling special enzymes to mix wit your boat gas to counteract the effects of storing the new gas in boats. Many of these are 4 cycle.

Andy

 

[gerard]

It doesn't "attract" water, it absorbs it.
It is primarily what "Dry Gas" (& similar gas line anti-freeze) is.
They enable water to be carried into the cylinder and turned to steam in the combustion process.
Look up water injection sometime.

The O/P stated that he keeps the trimmer indoors and the gas can sealed.
Ethanol won't "attract" moisture from humid air through the sides of a can.As to whether or not refineries and distributors feel they can relax their efforts to remove water on the basis that the additional ethanol will absorb it.... possible.
I doubt there is more ethanol in 87 vs 89 or 93 gas, though that may vary by brand name.

Kind of what I thought too, hence my skepticism but the water was in the gas and I certainly didn't put it there! (I should also mention that this is my two cycle mix, of which I made up two gallons with stabilizer since I don't use a ton of it it sits around a little longer. Maybe if you go through it quicker it isn't an issue. I only mix a gallon at a time now)

 

[LBrown59]

*I agree that there is probably not any difference in the amount of ethonol in 87 vs 89 or 93 gas. The ethanol definitely absorbs water. Just ask boaters. They are selling special enzymes to mix wit your boat gas to counteract the effects of storing the new gas in boats. Many of these are 4 cycle.

Andy

I'd say it's more a care and storage issue than a fuel grade thing.

 

[Matt_Jr]

The water most likely got in there when the tanks were being filled at the station. Probably done on a rainy day. I pulled four gallons of water out of a corvette last year, by running the fuel pump and running a line into a five gallon bucket. Then dumped four bottles of rubbing alcohol in it to get it started. Ran great after that.