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Ethanol percentage in gas

Ex Bonanza Bucko

Well Known Member
Does anyone know if there are differences in the percentage of ethanol in premium (92 octane) gas than in lower octane gas in California.

I would really like to know if there is any premium gas from a "main line" fuel company like Chevron of Shell that has less ethanol in it than some other gas in Goofafornia.

I have looked long and far on the net and found pretty much a big pile of obfuscation and potential fibs by both gummint and oil companies.

EBB
 
It's really very easy to test fuel for the presence and content of ethanol. If you're wondering whether California's 92 octane gasoline has more ethanol, then stop surfing and just test it for yourself.
 
I use the EAA test kit:

http://www.shopeaa.com/alcoholtestkitandquickchecksolution6mlbottlecombo.aspx

IMG_8592.JPG


It will detect ethanol and show the percentage.
 
Here is a simple test using only water. I have a plastic sports drink bottle that I use for this test. At the station where I get my premium grade from I have to make sure I run some fuel in to the tank before testing, since the lower grades have alcohol in them and they may be what was is in the hose before starting.

My Corvette Service Manual has the same method in it for the same purpose.

http://www.fifthaveinternetgarage.com/tech_tips/tech_tip_imageing.s/Fuel_Test_Inst.pdf
 
For what it's worth each station only carries two grades of fuel. The reason mid grade fuel is always halfway between premium and regular price is that it is a 50/50 blend. I assume that means everything is he same % ethanol as advertised on the pump.
 
Hey Rich - -

In Iowa, many stations offer 3 types. 87, 87 with Ethanol, and 91. Depends upon where you live.
 
I use the EAA test kit:

http://www.shopeaa.com/alcoholtestkitandquickchecksolution6mlbottlecombo.aspx

IMG_8592.JPG


It will detect ethanol and show the percentage.

Here is a simple test using only water. I have a plastic sports drink bottle that I use for this test. At the station where I get my premium grade from I have to make sure I run some fuel in to the tank before testing, since the lower grades have alcohol in them and they may be what was is in the hose before starting.

My Corvette Service Manual has the same method in it for the same purpose.

http://www.fifthaveinternetgarage.com/tech_tips/tech_tip_imageing.s/Fuel_Test_Inst.pdf

Just for clarification, the EAA kit has two methods for testing for ethanol. One is the water only method with a graduated sampler that not only indicates presence of ethanol but also percentage. The other is a dye that is added to gasoline to indicate whether or not ethanol is present.

I usually use the water method but the dye method would be very easy to use at the pump.
 
I Tucson, AZ I have a friend that has tested every batch he ever got. In Tucson they claim up to 10 %. The tester he uses is from Spruce. He always sees 6%-7% and only once 8%. So many places that say up to 10% or 15% really aren't up at full strength. Personally the engine doesn't care and if you can run ethanol in your tanks then what ever percentage we have here in the US isn't a big deal and for me isn't worth testing. It is what it is. They have been running concentrations of 23% down in South America for 2 decades and they haven't had a single problem with a Rotax. Rotax tested 10% and said it was fine and found no issues. I have talked to two people that have pulled two Rotax engines down with those 20%+ fuels with over 1400+ hrs. and no issues. Ethanol evils are way over hyped. If your car can run on them then the Rotax can. Your fuel lines are usually from the auto industry so that usually isn't a big deal so if your fuel tanks are good with it your good to go.
 
I Tucson, AZ "Ethanol evils are way over hyped."

Don't want to get into a pissin match here, but there's a lot of information out there provided by experts that disputes the "over hyped" statement. There's a little more to be concerned about than just tanks and fuel lines.
 
If it is so evil why run it in your car or motorcycle and never give it a second thought, your hoses or other components a second thought? Most of the US runs on it. The Rotax engine is motorcycle engine compared to a Cont. or Lycoming which is actually old technology.

Experts aren't always expert and rarely do real research. For the most part the experience with ethanol is in the owners that use it world wide. If it were evil we would have planes constantly falling out of the sky. The majority of the guys that have had problems and certainly there have been a few is with poor components (i.e. incompatible fuel tanks, poor hose choices or other components and contaminated fuel) For instance almost the entire US fleet of Flight Design's use 91 oct with ethanol. Yes there some that use 100LL and a few who can find 91 oct without ethanol. They have had zero problems. Your RV12's use ethanol and I have 5 that come to my shop. Many other LSA and experimental use fuel with ethanol. Experts may make things look good on paper, but sometimes real world experience trumps paperwork. Real world experience from around the globe shows that many hype the woes of ethanol with suspicions or unproven speculation. If the experts think 10% is evil and kills planes what would they think of the South Americans that use 23% and have no issues. I did a demo once and poured a glass of water in a fuel tank with 91 oct and ethanol. (I'm a retired HazMat tech from the fire department) No what happened? Nothing. It still ran, maybe not as BTU efficient as if it were pure fuel, but it ran just fine. Now do you want all that water in there, absolutely not because it can do other things, but to suck in that much water through the tiny fuel cap vent hole that is out gassing to start with would take years.
I maintain and maintenance at least 30+ LSA a year and all use 91 oct with ethanol except maybe 5-6 that use 100LL and not because they want to.

Hearsay of the ethanol evils as totally different from actual and real in use proof.
I hear hearsay 2-3 times a week, but have never seen any in your hand real life proof and some thing people blame on ethanol wasn't ethanol caused at all. I have been using ethanol laced fuel in my planes and a helicopter for 12 years and all the Rotax LSA at my field (KRYN) all use 91 oct with ethanol.
 
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Gas station owner

I am building an RV-3; I fly behind a 2200 Jabiru; and I also own a Mobil gas station in California. There are only two grades of fuel, premium and regular. The mid-grade is a 50/50 blend of the two. The percent of ethanol in each grade is always the same. In California the refiners can add up to a max of 10 percent. It usually is closer to 5 percent. I have never seen it higher than 8.
I have used premium auto gas for 2-years and 130 hours almost exclusively in the Jabiru with no discernible negative effects. In my experience I think we tend to make too big a deal out of the ethanol thing.
Respectfully,

Bill Newkirk
 
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