The International Cessna^® 170 Association

I did fail to mention that once the warning about using the ethanol fuel in small engines came out I stopped using it and switched to the 91 octane. So that could likely be why I have only had two small engine issues. When I took my zero turn mower in for some non carb work he said as long as it is not carb work as the warranty folks don't won't work fix issues related to ethanol fuel problems.

Justin, your lucky if the 91 octane doesn't have ethanol in your area. All mogas in my area has it in all octanes. There is no ethanol free MOGAS to be had within 50 miles of my house.

I really mean that first statement to have been a question and not a statement. Have I lowered the biggest risk of using MoGas if I am using ethanol free and us it in a timely manner?

juredd1 wrote:...I did a quick search but did not see when AvGas come about but was it after the time these planes were built. If so then what fuel did these planes run so well on back in the 50's? I am asking this as a questions as why not to use ethanol free fuel. I am sure the standards for AvGas are better than MoGas but were they better for MoGas back then if that is the type fuel used?

Justin

By the year BEFORE Lindbergh's flight to Paris the U.S. gov't had issued specifications for TWO types of aviation fuel and one for common "motor" gasoline.
By 1930 the U.S. Army had already specified 87 octane for aviation use.
By 1938 100 Octane aviation gasoline was specified.
Want more reading? http://mycommittees.api.org/rasa/jfm/Sh ... e%20US.pdf

Dang....there went another leg to stand on.

Thanks George.

Justin

George,
Your link above provides a lot of reading of which a great deal is quite interesting. Unfortunately, I am unable to enlarge the print to where it is easier reading for me.
One part that I have a difficult time trying to understand is the stated requirement of the US Army Air Corps and the exclusive use of 100 octane fuel starting in 1938. In my time in the Air Corps and the Air Forces, from 1942 and on during WWII, we used 73, 80/87, 91/98. and 100/130 octane fuels. Even tactical aircraft that I flew never had a higher grade of fuel than 91/98 until I got into the B-29. Those engines were working so close to the ragged edge that they couldn't be operated on anything less. There was an awful lot of less than 100 octane consumed in other than combat operations.

Yes, the article goes on to mention that British aeroplane requirements subsequent to the Battle of Britain created an Allied agreement to use 91 Octane for the duration. After the war, multiple octanes became available.

I'm sorry if it's too difficult for you to read all that article. I agree, the type is small, but the info on fuel development (particularly jet fuels and kerosene/gasoline mixes) is a really interesting story. (The U.S. Navy continued to use aviation gasoline even in jets well into the '60s for simplicity of shipboard supply. Eventually even they tired of the increased maintenance issues of leaded fuels.)

The wartime production of avgas eventually exceeded 20 million gallons per DAY! (Which explains why the stuff was so cheap throughout the 50s/60s....all those oil fields and refineries had excess capacity.) As the world recovered from the effects of WW-2, Korea, VN,... and worldwide increases in personal auto ownership blossomed... along came higher prices with the loss of excess capacity.

Then came 1973.... and you know the rest of the story.

(By the way... the Navy, for awhile added TEL (lead) to their aircraft over-the-wing... in order to avoid it's problems in equipment that did not need the octane, even despite the hazards of personnel contamination issues..... which confirms to me that my idea of having TEL added AT THE PUMP is not only viable...but probably a good solution to the EPA and transportation issues of Avgas.

I wish I could DE-select TEL in my Avgas at the pump.

But it is what keeps your valves lubed, George, TCP just keeps it from sticking...

Brad Brady wrote:But it is what keeps your valves lubed, George, TCP just keeps it from sticking...

I think you're only joking, of course. It's an old wives tale, the belief that lead lubricates valves. It actually builds up on valve stems and sticks valves, and sometimes forms glassy blobs that sit beneath valve seats and causes burned valves. (I still offer a case of good German beer to anyone who can come up with the proof that engine mfr's ever solved a valve-lubrication problem with the discovery of TEL (tetraethyl lead)....
....because it never happened. TEL was only added to fuels for the purpose of raising apparent octane to relieve detonation at higher compression levels.)

I have discontinued the use of TCP in my airplane as of about 4 years ago. I have not yet suffered any ill effects. I do lean in accordance with the Owner's Manual, without any benefit of EGT system. (I do clean or replace spark plugs each annual/100 hrs, and there does seem to be a slight increase in lead deposits in the spark plug wells I have to "vibrate" out, but no other deleterious effects so far.)

In another line-of-thinking... Those that endorse the use of MMO in their fuels in the belief it prevents valve sticking ... (usually believing the MMO claim that it "lubricates upper-cylinders"... whatever that is..).... I harbor a suspicion their subjective-positive experiences likely has nothing to do with lubrication. White Laboratories, a Dallas-area testing lab, tested the "mystery oil" in the 1980s and suggested that MMO is actually heavy kerosene with perfume and dye added. They also detected phosphorus along with a few other trace unknowns.
Personally, I've often wondered if MMO doesn't contain some amount of "EP" additives.... Extreme Pressure additives such as found in gear oils. The most common EP additive in lubricating oils is ...you guessed it.... tri-cresyl-phosphate.... otherwise known as TCP.

The problem is... MMO, if it does contain TCP.... does not reveal the concentration level, so it's guesswork as to how much should be added to fuel for the proper ratio. The other problem is, of course, approval-basis. The MMO folks probably don't want to spend the time, effort, and money on researching and obtaining approval for application of their product which carries such high Liability-risks.

While I personally do not use the stuff in my airplane, I do occasionally use it in small engine fuels, especially my portable emergency generator, which I usually service with Avgas for fuel-stability and fuel-system longevity-maintenance reasons. It's a voodoo practice. The Avgas is what I actually believe makes the difference, but I did once experience a stuck valve on a Honda and when I disassembled it, I found that white, powdery deposits had formed on the exhaust valve stem, which required me to remove the valve, polish the stem, lubricate it, and re-install it. After that experience, I used MMO in the generators avgas. I also do the Hokey-Pokey after refueling it as one of our former Members suggested. Seems to work.

My now-deceased friend Lewis Porter, former Huff-Daland Dusters mechanic (predecessor to Delta Airlines) once told me that in the days of turbo-compounded airliners, Delta and American were chief competitors in the Dallas/Houston-South American routes. The stuck valves and fouled spark plugs on those DC-7s they used were the main reason for dispatch delays.
Delta resolved the issue and developed a better dispatch reputation, but kept their secret closely guarded.
One day, Lewis noticed a new-hire on the ramp at Delta, and the man only stayed-on about a week, then was seen working over at American. The same week the FAA visited and discovered the 55-gallon drums of MMO Delta had been using to augment their refueling, and fined Delta some enormous fee for the time, and placed Delta under a temporary certificate action of some sort. All the MMO had to be removed from the airport property, and the dispatch-reliability of Delta deteriorated to about the same level as AA's.

Lewis recommended I use the stuff in my Aeronca Chief. I did as long as I used mogas (which was probably counter-indicative). I quit using mogas shortly thereafter.

I really don't have any heartburn with those who choose to use it in their personal, non-commercial airplanes, as long as it's a closely-guarded secret, but I don't endorse it.

Another automotive product which I use in my 1939 non-detergent-oil-only tractor (never in an airplane) is STP. The active ingredient in that is a zinc compound which uses 26 letters of the alphabet, some of them more than once. It is an "anti-scuffing" agent, often found in specialty lubricants.
The problem (again) in using it in airplanes is lack of approval, and one engine mfr specifically warns against zinc in their radial engine because it causes thrust-bearing failure.
I mention this because I occasionally get a query about it's use, and I warn against it. Our C145/O300 engines have large friction-bearing surfaces designed into them and they do not need nor require any special lubricants. Ordinary AD aviation oil is all they need.

Remember, this engine still owns the world's record for longevity in a continuous operation challenge, which was established back in 1959.
Another team recently tried to beat that record using more modern methods and lubricants, etc., with a Lycoming engine... And failed.

The record-setting airplane, a C-172 with a 145 hp Continental, is still hanging above the baggage claim area in Las Vegas since it's famous flight, in which it lifted off in 1959 and landed over two months later in 1960 after flying beyond the original TBO without a proper oil change and on the same spark plugs. (They used 80/87 Avgas.) Bottom line: Don't mess with success. Use ordinary AD aviation oil, no additives necessary.

How far back does the use of Alcohol in car gas go Probably not as far back as we think of this photo, notice the early .com use in a sign in the back ground.

Henry Ford promoted the use of 100% ethanol for motor fuel way back in the 1930's. He particularly wished to promote farmers use of it in their Fordson and Ford tractors, recognizing that raising corn for fuel was a double benefit to farmers. (In fact, he recognized that the grain from corn could be used for food while the silage could be used to produce ethanol, thereby using the entire plant.) He also recognized that more horsepower could be obtained from higher compression engines and that ethanol could withstand higher compression without detonation/knock than could the ordinary gasoline available at that time (typically less than 76 octane.)

But a powerful alliance between DuPont chemical and General Motors and Standard Oil overpowered the conversation. Standard Oil wanted gasoline to be the "fuel of the future" and GM had a holding in Ethyl Corporation and their business partner DuPont had the patent on a chemical known as tetraethyllead, which provided apparent increase in octane for gasoline. Standard Oil (and the DuPont family in particular) had powerful political connections and Ford had a reputation as a "crank" with politicians. (Remember that he co-financed and promoted an anti-Semitic book sympathetic to the Nazi view prior to the war.)

Henry lost out in his attempt to promote pure ethanol for automobile fuel, and Ford and GM were less than amiable competitors.

After reading all of the above,it is really hard for me to realize how incredably lucky I have been after using mogas, even that containing alcohol, for all those years on a variety of engines, and never once had a problem. Just one of the advantages of leading a pure and exemplary life, I guess.
I'll bet that if I was still on active duty in the Air Force, the Chaplin, bless his heart, would point to me as the guy setting an example to strive for.

WOW, I hope you are the example for others to behold. I do know you have many life experiences to share. I hope it is also documented.

John