How To Check For Ethanol In Gas

[GF]

Step1:
Collect a fuel sample from your car's fuel supply. I use a clean 1 liter pop bottle that is clean and dry (so you wont contaminate your sample).

Step2:
Pour 90 ml of your fuel sample into the 100 ml graduated cylinder. Add 10 ml of water to the cylinder and cover the top with your finger and shake.

Step3:
Let the fuel sample set for 10 to 15 minutes. The alcohol will combine with the water and separate from the fuel. Read the line where it separates.Now comes the calculation, with 100 ml = 100% Looking at the cylinder, the way we would read this is: The line is on the 53 and we know 10% was water to begin with. The water will settle to the bottom because water is heavier than gasoline. 53-10=43 This sample would be 43% alcohol, which would be way to much for a 10% blend and most cars would run very poorly if they started at all.

[beenthere]

Step1:
Collect a fuel sample from your car's fuel supply. I use a clean 1 liter pop bottle that is clean and dry (so you  ?? ?? contaminate your sample).

Step2:
Pour 90 ml of your fuel sample into the 100 ml graduated cylinder. Add 10 ml of water to the cylinder and cover the top with your finger and shake.

Step3:
Let the fuel sample set for 10 to 15 minutes. The alcohol will combine with the water and separate from the fuel. Read the line where it separates.Now comes the calculation, with 100 ml = 100% Looking at the cylinder, the way we would read this is: The line is on the 53 and we know 10% was water to begin with. The water will settle to the bottom because water is heavier than gasoline. 53-10=43 This sample would be 43% alcohol, which would be way to much for a 10% blend and most cars would run very poorly if they started at all.

Did you leave out a word in step 1  ??

Thanks for the method. Seems one could do that right at the pump...by showing up with 10ml of water in the grad. cyl, then fill it with gas...and shake and read.

[GF]

Corrected the typo.  Just seen on the news also this week in Okla the first class action lawsuits have been filed against Love's, 7-11 and Quick Trip for mixing 5% to 15% ethanol in fuel without notifying customers or lowering the price.  Apparently these chains according to the lawsuit have been adding ethanol since 2005.

[treenail]

Recently, I have begun to notice that the Mobil stations around this area all have a notice on the regular gas selection that says there is 10% ethanol blended into it. Have also noticed that the other stations around here don't seem to indicate on the pumps anywhere. For sure, my vehicles, motorized equipment, etc. are not running as well lately. Interesting.

[logwalker]

Let the fuel sample set for 10 to 15 minutes. The alcohol will combine with the water and separate from the fuel. Read the line where it separates.Now comes the calculation, with 100 ml = 100% Looking at the cylinder, the way we would read this is: The line is on the 53 and we know 10% was water to begin with. The water will settle to the bottom because water is heavier than gasoline. 53-10=43 This sample would be 43% alcohol, which would be way to much for a 10% blend and most cars would run very poorly if they started at all.

A couple things I noted on your methodology. You are starting with 90 ML of fuel so you need to divide the 43/90 to be accurate. Also when water and alcohol mix they combine and take slightly  less volume together than when separate so this would cause inaccuracy also. Not trying to be negative, just accurate. Another interesting side effect of the mixing of the H2o and Alcohol is a release of energy in the form of heat. Joe

[John Mc]

A couple things I noted on your methodology. You are starting with 90 ML of fuel so you need to divide the 43/90 to be accurate. Also when water and alcohol mix they combine and take slightly  less volume together than when separate so this would cause inaccuracy also.

Yes. To be more accurate, you need 1 part water (10 ml) to 10 parts fuel (100 ml). After subtracting of the 1 part water from the reading, you'll get pretty close to the percent of alcohol in the mixture. (This doesn't account for the water/alcohol mix taking slightly space as logwalker noted... I hadn't heard that one before.)

We do this test when burning autofuel in piston aircraft engines... though in that case, I'm not too concerned about the actual percentage. Anything that's even noticeable means it's no good for aircraft use.

John Mc

[GF]

The topic was only posted for a general guideline and not for 100% accuracy, thought it may help some people out on checking to get an idea if their gas contains.

[John Mc]

You're right, I guess we're getting a little picky. I usually don't even bother to measure how much is there. I just mark the water line, add the fuel, shake, wait and see if the "water level" increased. If it increases at all, I won't put in in the plane. If the increase is only slight, I might mix it up to use in the chainsaw, especially if I'm going to use it up fairly soon.

John Mc

[logwalker]

I hope I didn't come across as being too picky, it is just that the amounts that are allowed by law are specific and if you are going to report them it helps to be accurate. I do appreciate the original post's intent and usefulness. Joe

[GF]

LW, 
   You didnt come across wrong, I was just wanting to help out with something that has about zero cost so people can check to see if gas checks positive for ethanol.  Anymore people in my area are comapling about how the cars are running rough etc, but when they get gas at other stations they run OK.  I guess if you car does not run to well after filling up first thing to check would be the fuel before taking it to a mechanic and paying to see what may be wrong with it.  Money is tight for eveyone and every dollar helps out.

Gary