Autogas in Aeronca Champ?

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Cardiff_Kook

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Cardiff_Kook
I was checking out friends champ the other day and thinking of buying. Very well maintained. It is set to run on autogas. We are in CA so the autogas has ethanol I would imagine which I think is an issue.

He said they mix the auto with AVgas 50/50 and have been doing it for 15 years without an issue.

Is this cause for concern? He is very knowledgeable and meticulously maintains his stuff so I would I be surprised he would do something that would damage the aircraft.

PS- I'm a full noob.
 
The STC for auto fuel does not allow use of gasoline with ethanol.
There may be rubber parts in the fuel system that are not compatible with ethanol - there have been actual in flight engine failures.
 
You can go to pure-gas.org to find gas stations that sell ethanol-free gas. There are 23 stations in California, so not many, but there may be airports that stock the stuff as well.

edit- I got beaten to the answer by a few seconds. Arrgh
 
Learn how to check for alcohol in MoGas sources. Easy. Sometimes stations (and FBOs too) will end up selling E10 as E0 Mogas since E10 is subsidized and E0 is not.
 
Pretty easy to test. The E10 tastes better.
 
The old Champs had Stromberg carbs on them, and that carb had a series of float valve types. The earliest was a stainless valve, then they made a stainless valve with a rubber valve tip, and the final version was a Delrin valve. The rubber tip on the second version does not like ethanol and can swell enough to shut off the fuel flow into the carb and kill the engine.
http://www.bowersflybaby.com/tech/stromberg needles1.pdf
 
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Ethanol will dissolve the shellac on the fuel gauge cork, too...
 
Auto gas will also stain the crap out of your paint and make your plane look ugly if you spill and or have any minor leaks.
 
Unless you are somehow stockpiling it, are you really saving much by using MoGas? Especially in California, where the refiners rip us off to the tune of about a dollar a gallon (it isn't even close to all taxes, regardless of what people tell you)? Going out of your way to get MoGas will ultimately result in burning more fuel. We can technically put MoGas in the E33 - I'm not going to do that though.
 
N1120A said:
Unless you are somehow stockpiling it, are you really saving much by using MoGas? Especially in California, where the refiners rip us off to the tune of about a dollar a gallon (it isn't even close to all taxes, regardless of what people tell you)? Going out of your way to get MoGas will ultimately result in burning more fuel. We can technically put MoGas in the E33 - I'm not going to do that though.
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Especially considering the fuel flow of a Champ. ;)
 
If I could get E0 mogas here I'd run it or a mixture, at least in the summer when it doesn't sit in the tanks long. My O-290 doesn't like all that lead.
 
It really isn't the issue of mogas-alcohol vs 100LL that is the problem for our 1930s Depression era engines. It is the crap that 100 LL isn't NO lead, it is 2 ml/gallon of tetraethyl lead that will foul the plugs and pollute the atmosphere with cancer-causing lead. Maintenance and ecology. Pick one. And the alcohol that Congress subsidizes to midwestern farmers to grow corn that is converted to alcohol, the alcohol that tears your rubber and synthetics apart inside your carburetor and fuel lines. What an absolutely anti-symbiotic relationship.

For those of you who say that you aren't interested in politics, rest assured that politics is interested in you.

Jim
 
Yes had an engine quit right after take off, good thing there was a field straight ahead, my partner had put auto gas in the tank and did not tell me, the fuel gauge leaked and it stunk up the cockpit, on 100L,no leaks go figure, the issue was the carb.
 
Cardiff_Kook said:
I was checking out friends champ the other day and thinking of buying. Very well maintained. It is set to run on autogas. We are in CA so the autogas has ethanol I would imagine which I think is an issue.

He said they mix the auto with AVgas 50/50 and have been doing it for 15 years without an issue.

Is this cause for concern? He is very knowledgeable and meticulously maintains his stuff so I would I be surprised he would do something that would damage the aircraft.

PS- I'm a full noob.
Click to expand...
 
I have seen over the years, stuck valves on many of these small Continental engines A65,C85 That used 100LL as a steady diet,(always seems to be the exhaust valves that stick) mine included. I switched to non ethanol mogas at a 75/25 ratio in my Champ with the C85. I have been told and believe the amount of lead in 100LL is the main problem for the valves on these old engines. For me non ethanol mogas is locally available, 5 years and about 500 hrs use. So far so good.
 
N1120A said:
Unless you are somehow stockpiling it, are you really saving much by using MoGas? Especially in California, where the refiners rip us off to the tune of about a dollar a gallon (it isn't even close to all taxes, regardless of what people tell you)? Going out of your way to get MoGas will ultimately result in burning more fuel. We can technically put MoGas in the E33 - I'm not going to do that though.
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Don't they put the amount that is tax on the pump, and on the receipt? It must be displayed on the pump in many states, including mine.
 
Kenny Phillips said:
Don't they put the amount that is tax on the pump, and on the receipt? It must be displayed on the pump in many states, including mine.
Click to expand...

They post excise on the pump, but sales tax is also included. With all taxes, including sales and excise, gas should be around $2.70-2.80 a gallon in CA. We know it's much more than that.
 
I've been using MOGas since the 1990s in a PA-28 and since 1995 in my Aeronca. Not a problem, just had a rubber tip Carb needle replaced with a stainless steel one. MOGas is next to airport at 3.99 gal while 100LL is 5.95. Even at 4.2 GPH it adds up. The engine runs fine. The only rubber in the fuel system for the A-65 is the gas line from the gascolator to the engine and the needle. Everything else is metal. Just keep away from the ethanol. A lot of boat docks sell ethanol free too. The ethanol is added at the truck loading dock, since the gas companies don't want it fouling up their own rubber seals. It's not a worry if there isn't any ethanol in it.
 
An FBO at Duluth thought he had "certified" MoGas fuel that I tested to be about @ 5% ethanol after my hangarmates C-140 stumbled over Lake Superior. I called the manager, described the water test which he was unaware of. He had relied on the certification that came from the bulk truck driver. That fuel load had been used for about 6 weeks. Later he said the credit card people wouldn't disclose the user N numbers and addresses.

I used MoGas almost exclusively in my 172M for 15 years and my J4 for 5 years. I checked each load for ethanol, but never found any from the two local marine sources
 
Dan Thomas said:
The old Champs had Stromberg carbs on them, and that carb had a series of float valve types. The earliest was a stainless valve, then they made a stainless valve with a rubber valve tip, and the final version was a Delrin valve. The rubber tip on the second version does not like ethanol and can swell enough to shut off the fuel flow into the carb and kill the engine.
http://www.bowersflybaby.com/tech/stromberg needles1.pdf
Click to expand...

strangebird said:
Yes had an engine quit right after take off, good thing there was a field straight ahead, my partner had put auto gas in the tank and did not tell me, the fuel gauge leaked and it stunk up the cockpit, on 100L,no leaks go figure, the issue was the carb.
Click to expand...

Both of the above posts are accurate. The Delrin tip can swell as well. I have learned a bunch about carburetors and fuel since buying a Champ last spring, Mostly the hard way. Bottom line is that unless you know you have a stainless tipped valve do not use car gas, even ethanol free. It will swell that tip and F up your carb and possibly ruin your day. I have used ethanol free gas in my Cessna for several hundred hours with no issues, but the Stromberg carbs in Champs are just different. Also the floats are more sensitive. 100LL has a slightly lower specific gravity than car gas and the carb should be "tuned" to one or the other.

Pete
 
These engines like in your Champ were designed for 80/87. 100LL is only low in lead compared to the old 100/130 grade it replaced. It still has over four times the lead that 80/87 did (and even old premium auto gas). The autofuel STCs (there are two fort his aircraft/engine combo: Petersen and the EAA) specifies the octane (usually not a problem with the A-65) and that it has no alcohol. You can run anything from straight mogas to straight 100LL under the STC. 50/50 is probably way overkill. A tank full of 100LL every once and a while to contribute some lead to the valve stems is probably sufficient.

There's several websites like puregas.com that list your local non-ethanol gas stations. We're fortunate here as we're very close to a major lake (ethanol is bad news in a marine setting) that it's not hard to come by.

Petersen (https://www.autofuelstc.com) has more information on this than you probably care to know. The EAA STC info is here (https://www.eaa.org/eaa/pilots/EAA-STC-Program/auto-fuel-stc).

Note you can't run autofuel legally without one of these STCs even if it is just a "paper" STC in the case of the Champ/A-65.
 
I've known guys to run all kinds of airplanes on auto gas. Of course, now all the gas has booze in it. I'd have to go so far out of my way to get booze-free auto gas that it just isn't worth it, so I didn't worry about the STC when I got my airplane. Had I auto gas available I might have chosen a different ride.
 
With the problems getting ethanol free mogas (not available where I live, even at marinas), I wish there'd be some movement on the new 94UL avgas...
 
weirdjim said:
It really isn't the issue of mogas-alcohol vs 100LL that is the problem for our 1930s Depression era engines. It is the crap that 100 LL isn't NO lead, it is 2 ml/gallon of tetraethyl lead that will foul the plugs and pollute the atmosphere with cancer-causing lead. Maintenance and ecology. Pick one. And the alcohol that Congress subsidizes to midwestern farmers to grow corn that is converted to alcohol, the alcohol that tears your rubber and synthetics apart inside your carburetor and fuel lines. What an absolutely anti-symbiotic relationship.

For those of you who say that you aren't interested in politics, rest assured that politics is interested in you.

Jim
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You left out the part about increased fuel consumption due to alcohol. ;)
 
ORich said:
I have seen over the years, stuck valves on many of these small Continental engines A65,C85 That used 100LL as a steady diet,(always seems to be the exhaust valves that stick) mine included. I switched to non ethanol mogas at a 75/25 ratio in my Champ with the C85. I have been told and believe the amount of lead in 100LL is the main problem for the valves on these old engines. For me non ethanol mogas is locally available, 5 years and about 500 hrs use. So far so good.
Click to expand...
I must’ve gotten 100LLTAE (Lower Lead Than Anybody Else)...1400 hours on an O-300 with zero lead fouling/valve issues.
 
I can find E free gas but its only 90 octane. STC's on higher compression engines want 91 octane. I cant find that. My guess is that when you take the alcohol out of 93 you get 90.
 
Scott MacMoyle said:
I can find E free gas but its only 90 octane. STC's on higher compression engines want 91 octane. I cant find that. My guess is that when you take the alcohol out of 93 you get 90.
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Indeed alcohol increases octane. This is why in some places you can't even get regular e-free gas because the base stock isn't high enough octane.

Indeed the A65 and the like in the airplane the poster is talking about only needs 87 AKI (As you know the AKI is similar to, but differently calculated than the Avgas octane numbers).
As I say, I'm in an enlightened area because we can easily get 93 Octane e0 here. Of course, if you're in a metro area that mandates oxygenates you're going to have a problem as ethanol is all that is practically used these days (MTBE would work fine in aircraft, but do to other environmental concerns: gas station tanks leaking into the groundwater, it's been phased out).
 
auto gas is always a highly opinionated subject. I myself am pro auto gas. Ive used it on my AA1A and my friend put the blue stuff in his and every 50 hours his lower plugs were fouled with lead. He spent hours cleaning them. He could not be persuaded. some people just think the blue stuff is some kind of magic elixer. The truth is that the stuff really is inferior fuel. Way too much lead in it. Ethanol is stupid too. This is what happens when the government gets involved with our gas. I love the youtube video of the guy who washes out the alcohol and puts it in his plane.
 
Scott MacMoyle said:
auto gas is always a highly opinionated subject. I myself am pro auto gas. Ive used it on my AA1A and my friend put the blue stuff in his and every 50 hours his lower plugs were fouled with lead. He spent hours cleaning them. He could not be persuaded. some people just think the blue stuff is some kind of magic elixer. The truth is that the stuff really is inferior fuel. Way too much lead in it. Ethanol is stupid too. This is what happens when the government gets involved with our gas. I love the youtube video of the guy who washes out the alcohol and puts it in his plane.
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Is that for real?

Sent from my Pixel 3 using Tapatalk
 
Another concern is the amount of residual water that is still remains dissolved in the gasoline after the treatment. If that hooch is severely chilled during flight, the mix will have water particles that appear as snow. Only a tiny amount of snow can block the gascolator after a longer flight. (DAMHIK)

Adding some minor amount of water-removing alcohol (yes, like HEET) back into the fuel could keep the solid ice/snow from forming.

there still remains the issue of residual octane. I know though that it worked for my lawn mower.
 
Ethanol and water will bond, that is how you can test for it.

And of course it reduces the octane, That is why the Ethanol is in there to begin with. It is filler :)
 
I run ethanol free gas in my 150 without any issues. Yes there are some downsides as mentioned but for me the cost savings is worth it.
 
N1120A said:
are you really saving much by using mogas, especially in California, where the refiners rip us off to the tune of about a dollar a gallon.
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Well, we do have the cleanest burning gasoline in the world... and it cost billions of dollars to modify refineries to make that stuff... so it's not surprising that it commands a premium in the marketplace. Most refiners in the world can't make the stuff, or they'd be importing it to California to compete, given the price premium.

I'm heartened by the progress... I remember living in Silicon Valley in the 70's (before it was called that) and then later in the LA basin. It was a couple times a year we could see the surrounding mountains, and there were days it made you sick to breath the air. Now, it's only a couple days a year that you CAN'T see the mountains, and illness from smog is nearly unknown. I think if you do the utils math, you'll find that the millions of people whose daily living was made better was worth the investment.

Of course, if you live on a mountaintop far from urban areas in California, but have to pay the fuel premium for regulatory reasons, that's annoying... but then, there are prices to be paid to being part of a larger society... and most often benefits too (advanced medical care comes to mind...)

Paul
 
weirdjim said:
2 ml/gallon of tetraethyl lead that will foul the plugs and pollute the atmosphere with cancer-causing lead
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Hi Jim,

Note that lead is very heavy compared to water. (water is why you may be thinking a gram is a milliliter). 1.6 grams of lead per gallon is one milliliter, and a typical additization rate for 100LL... 2 grams/gallon is the maximum per the 100LL specification.

I think you pretty much have to take a bath in lead to raise your cancer risk... the most concerning risk is that very small doses of lead has a negative impact on brain and nervous system function, and those can be life long effects for those exposed as infants or children... There's no safe dose of lead with respect to neurotoxicity. Animal studies show that it takes substantial lead exposure to induce cancer.

That's why a number of us are working very hard to bring unleaded avgas to market that performs as well as 100LL, or performs better in some respects. The FAA is working hard too, but they're sometimes misguided (bad science). The FAA has never approved a fuel before, they only approve engines and airframes to operate on ASTM specified fuels. So the FAA doesn't have much bench strength in that arena.

Paul
 
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perhaps, but none of that has anything to do with ethanol. Ethanol is all about money and politics under the quise of protecting the enviroment and avgas is just allot of lead which was supose to be ruining the eviroment anyway. Both fuels are garbage in my book. Cars get less milage with ethanol so you got to burn more of it.
 
I am sure it is legit, but I wonder how much of a hit the octane takes.
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About 3 numbers

nrpetersen said:
Another concern is the amount of residual water that is still remains dissolved in the gasoline after the treatment.
Adding some minor amount of water-removing alcohol (yes, like HEET) back into the fuel could keep the solid ice/snow from forming.
Click to expand...

Caution! HEET comes in two flavors, methanol and isopropanol. The methanol will attack the aluminum in your tanks and fuel system. Very, very bad idea.

Both Lycoming and Cessna, for instance, do approve isopropanol in the fuel system, up to 2%. It won't affect octane, but it will co-solvent the water to carry it through the combustion process without freezing or separating out. You can buy just anhydrous isopropanol at the drugstore or hardware store, but do NOT add rubbing alcohol, which is 30% water...
 
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