Just an update, I called the station I go to and asked them. They do use 85% year round, but i wasn't 100% confident in his response. There does seem to be quite a bit of discussion around the 'net about E70, so maybe DC isn't in an area that warrents 70% mixture.

 

My E85 station is in San Diego, so they don't really have any reason to make it E70. However, I am working on converting my car to run on pure E85. A new station is opening up by my house in March, so I need to get ready!

 

Isn't that an oxymoron?

 

haha. I mean as opposed to part E85 part E5.75.

Here's an interesting bit I found on ethanolforums.com regarding the percentage of ethanol in E85 and E10:

 

I just got my Pyrex 100ml graduated mixing cylinder in the mail.
( Tol. +/- 0.6mL )
I am going to be testing the "fuel" blends in MN, IA, NE, CO, WY, KS very soon ( and other states as I have a need to be there.... ). Of course what I find in MN wouldn't apply to San Diego... but if MN has 85% ethanol in their E85 in the dead of winter ( -20'F ) then it would be more likely that the E70 is not required for winter in the rest of the U.S.

Check back here often.
I should have my first test done later today.
The only thing I will be able to measure is the gasoline/ethanol proportions. I will have no clue to the actual "quality" or btu content, or anything like that. -John

 

If I understand the process, you mix a finite amount of ethanol with a finite amount of water and the ethanol leaves the gasoline and joins the water column, right?

If so, you might 'decant' the gasoline into a transport container and using a small gasoline engine, measure how long a small gasoline engine runs on that quantity of fuel. Higher energy content gasolines will run the small gas engine longer. For example, a small portable generator that runs a heater and clock that is reset to 12:00 for each test. When the clock stops is the relative amount of energy from that sample of gasoline.

GOOD LUCK!
Bob Wilson

 

Yes, later today, I am going to add 50ml of pure water to 50ml of E85, and see how much petrol "floats to the top".

I was just thinking of what to do with my 100ml after that.
I don't want to pour it on the ground or down the drain.
I figure I will try to pour the top layer ( presumably gas ) back into my gas tank... the rest? Mostly water with some ethanol???

Ideas?

 

NO!!!

Pour it in a small gas container and when you have time, separate them at home. Use the gas in a lawn mower or if you can get all of the water out, pour the pure gas back into the tank.

I would recommend Googling "aviation gas water" to understand why it is important to keep any form of water out of the tank . . . really important. But the same references should include field techniques for separating the water out and leaving usable gas behind. Here are some useful hints:

http://yarchive.net/chem/gasoline_dewater.html
http://www.slyasafox.com/newsletters/august2003.html
http://www.mit.edu/people/robot/diesel/index.html

You really don't want any water coming close to the tank.

Bob Wilson

 

Yes but......

I'm using 30-40% ethanol in my car gas tank.... which.... dissolves water... water is miscible in ethanol, and vise-versa.... the ethanol molecules will "pull" the water through the engine and harmlessly out the tailpipe.... In Europe, many places use only 180 proof, or 10% water in their cars! Really!

Water and pure gas, or water and aviation fuel is a no go.
-John

 

Okay... here's the results of test #1 taken from this pump in S. Minnesota.



Here's my supplies:



Here's what it looks like after mixing 50ml "E85" with 50ml water and allowed to stand ~15 minutes:



The fuel was clear and colorless to start. It looked just like distilled water.
After, both mixtures were "milky".
After sitting for 3 hours, the top ( gasoline ) layer clarified. The alcohol/water mix stayed milky.
After sitting for 24 hours, both layers clarified. Maybe the milkyness was just trapped air?

And here's the math from a formula given in an earlier post:



So now we have the "legal" question of why is that pump labeled "minimum 85% ethanol" when it looks very clear that is not true?

Now I must apologize for posting incorrect graphs earlier.
I did not have "45% ethanol" in my tank this past tank.
Without testing, just by math, I used E26 and E40 respectively. ( not E30 and E45 )
I have the same data... just the labels are changed.... lower.
-John

P.S. I called the station owner and he didn't know what the ethanol blend was, or when it changed but he "believed" it went down in winter ( less ethanol, more gas ) "to keep it from freezing".

I called KwikTrip corporate HQ, and to my amazement, I got transfered to someone at the top, or near the top right away. Without telling him of my "experiment" he said right away that they sell E70 in winter, based on regional guidelines, and that it transitions to E75, then E80, then E85 only in summer. I said "Great! That's what I was reading online. Then I told him about the "Minimum 85%" sticker. He said right off that was a mistake, and the label should read "maximum 85% ethanol". Much to my surprise, he said he was going to call "engineering" and get them out on the road to change the stickers.

I asked if he would like an email copy of the photo, (above) and he said I didn't need to do that, but if I wanted to, he would forward the photos to engineering so they knew what to look for.

So great customer service... but that means tracking MPG is more difficult... since the transition from winter blend to summer blend varries by state.

I wonder if people with FFV who use exclusively E85 year round, get the same MPG year round?
Would the extra 15% gas in winter offset the cold effects?
I wonder if E85 users have a much flatter graph anually than the rest of us?

Also some good news is... my simple test looks like it works fine, since the corporate HQ does confirm they are currently selling E70 in my area.