Gasohol

In rec.aviation.owning Morgans wrote:

"Peter Dohm" wrote

Really, the only way that I know to correctly "do the science" is to
purchase a small amount (perhaps a liter) of anhydrous ethanol from a
medical supply and perform a series of tests on a variety of
samples--including samples of known pure and dry avgas and mogas. For the
moment, I am unwilling to undertake the project, and also I believe that
Clare and Bob are correct.

How sure are we that the gasohol in service station tanks contain no water?

Is it possible that all tanks containing gasohol contain at least some water
dissolved?

Is it a certainty that the alcohol added to gasoline contains no dissolved
water?

I don't know the answer to any of these questions. Does anyone know, for
CERTAIN, any of these questions?

My guess is that all service station tanks, (unless they have never had
straight gas, and that they are BRAND NEW) have had an opportunity to get
some water in their tanks. If that is the case, and you put gasohol in
them, the gasohol samples will contain some dissolved water, and the seltzer
test will work.

If that is the case, doing a scientific test with clean gas and adding water
free alcohol will prove nothing.

Finding water free alcohol is basically impossible.

Alcohol will absorb about 2-3% water by volume as soon as it is exposed
to normal air, and that is what you will find in a medical supply
alcohol that is about 98%..

So if everything is kept as dry as possible, you can expect gas that
is 10% alcohol to be at least .2% water minimum.

Whether .2% water is enough to fizz an Alka-Seltzer tablet I have no idea.


--
Jim Pennino

Remove .spam.sux to reply.

Whether .2% water is enough to fizz an Alka-Seltzer tablet I have no idea.

I don't know the answer to any of these questions, but I've run almost
9,000 gallons of mogas through Atlas' Lycoming O-540, without a
burp.

In that time, I would be willing to bet that SOME ethanol-polluted
gasoline has run though his veins. It almost seems inevitable.

Personally, I am skeptical that gasohol is going to harm my 1974-
vintage aircraft. I use the damn stuff in every other gasoline engine
I own, including my 1986 Goldwing, my 1995 Toyota, my 1995 Ford van,
my 1997 Subaru, my 2000 Mustang, my three lawn-mowers, my two yard
blowers, and my one snowblower -- ALL without problems.

But, hey, if the FAA says it's bad, I gotta believe 'em -- so I test
every tank for alcohol.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

"Jay Honeck" wrote

Personally, I am skeptical that gasohol is going to harm my 1974-
vintage aircraft. I use the damn stuff in every other gasoline engine
I own, including my 1986 Goldwing, my 1995 Toyota, my 1995 Ford van,
my 1997 Subaru, my 2000 Mustang, my three lawn-mowers, my two yard
blowers, and my one snowblower -- ALL without problems.

But, hey, if the FAA says it's bad, I gotta believe 'em -- so I test
every tank for alcohol.

No doubt that you engine doesn't give a crap, but your fuel system could be
a different story.

I have seen pictures of fuel line swollen to the size of sausages, and who
knows what the other rubber parts (O-rings, fuel bladders, if you have them)
would look like, and how much alcohol it would take to get it to swell.

I think you are wise to keep on testing. If it were me, I would want to
know if the seltzer test worked as reliably as the add water test, and how
the seltzer would work on a fresh batch of alcohol.

Perhaps you can catch the gas tanker starting to fill a station's tanks, and
get a sample of gasohol right off the tanker, where it is less likely to
have gotten mixed with water, from storage tanks.
--
Jim in NC

The water line test works consistently and, if you have the graduated tube
from Petersen will give a fairly accurate percentage. Except for here, I
have never heard of the Alka Seltzer test.

mike

"Morgans" wrote in message
...

I think you are wise to keep on testing. If it were me, I would want to
know if the seltzer test worked as reliably as the add water test, and how
the seltzer would work on a fresh batch of alcohol.
--
Jim in NC

On Sun, 3 Jun 2007, Morgans wrote:

I have seen pictures of fuel line swollen to the size of sausages, and
who knows what the other rubber parts (O-rings, fuel bladders, if you
have them) would look like, and how much alcohol it would take to get it
to swell.

I'm no expert on the matter, but it's my understanding that that sort of
damage is done by methanol, as used in the early gasohol, but not by the
ethanol that's used in more recent times. Is that incorrect?

-Dan

I've heard that too, but it doesn't really matter since either invalidate
the STC and nobody is pursuing a STC to distinguish between them.

'Tis a true bummer.

mike

"Dan Youngquist" wrote in message
hell.org...
On Sun, 3 Jun 2007, Morgans wrote:

I have seen pictures of fuel line swollen to the size of sausages, and
who knows what the other rubber parts (O-rings, fuel bladders, if you
have them) would look like, and how much alcohol it would take to get it
to swell.

I'm no expert on the matter, but it's my understanding that that sort of
damage is done by methanol, as used in the early gasohol, but not by the
ethanol that's used in more recent times. Is that incorrect?

-Dan

"Dan Youngquist" wrote in message

I'm no expert on the matter, but it's my understanding that that sort of
damage is done by methanol, as used in the early gasohol, but not by the
ethanol that's used in more recent times. Is that incorrect?

I don't know about that.

I did think I understood that the problem with gasohol for airplanes was
incompatibility with some rubber parts of the fuel system.
--
Jim in NC

On Tue, 5 Jun 2007, Morgans wrote:

I did think I understood that the problem with gasohol for airplanes was
incompatibility with some rubber parts of the fuel system.

That's what I've always heard too, but I've never been able to get anyone
to back it up with info about SPECIFIC parts that are in danger. In
particular, I'd really like to know what SPECIFIC parts I have to change
in my IO-360-A1A's fuel system so I don't have to worry about alcohol.
(It's in an experimental, so legality isn't an issue.) At the same time,
I see all manner of decades-old cars & trucks running for many years on
gas that's part alcohol, with all original fuel system parts, with no ill
effects whatsoever. So I'm pretty close to writing off the whole ethanol
fuel system damage thing as an old wives' tale, but not yet willing to bet
the farm on it.

-Dan

"Dan Youngquist" wrote

That's what I've always heard too, but I've never been able to get anyone
to back it up with info about SPECIFIC parts that are in danger. In
particular, I'd really like to know what SPECIFIC parts I have to change
in my IO-360-A1A's fuel system so I don't have to worry about alcohol.
(It's in an experimental, so legality isn't an issue.)

Well, let's think about it.

I'm not an A&P, and have never torn an airplane carb or injector or fuel
pump, or ..... apart. Nevertheless, we can take some very educated guess,
and hopefully, some others with specific knowledge can jump in with some
specifics of the systems.

Let's look at the fuel system, from tank, all of the way until it goes
"bang." (the gas in the fuel system, that is!)

Fuel tank. Not a bladder, in an experimental, I would guess. Is it sloshed
sealed? Some sloshes will definitely NOT hold up to alcohol. Some will.
Is it sealed with other seam sealers? Again, some will hold up to alcohol,
and some will not. What did you use, if you did use them?

How about the seals or O-rings from the tank to fuel line fitting? What did
you use there? My suggestion for this, and most all of the other
replaceable parts, is to get an exact replacement and soak it in some E- 85.
If that does not cause the part to do strange things, 10% gasohol should not
cause a problem.

Fuel line, and flexible transitions, if used? Again, test what you used, or
find the manufacturer's recommendations, based on tests.

Fuel Valve. Lots of O-rings, there. Will they test alright?

Oh, back up. Fuel level indication sender, or sight glass and connections.
Test them.

Fuel pump, both electric auxiliary, and engine driven fuel pump. Use
manufacturer's recommendations, as there are so many variables, possibly
more in an electric. The engine driven pump recommendations will probably
not allow gasohol, but you, or someone who knows how could tear one down,
and soak test all of the non metal parts.

Gasolater and other filters. Test, to verify they will hold up.

Injector controls, spiders, and O-rings in all of these should be verified.
All of the non metal parts if it is a carburetor, for some people.

Then the injectors themselves will need a manufacturer's recommendation, or
a test.

Does that cover it all? What did I miss?

How about everyone, and you, Dan? Do you think this kind of step by step
investigation would uncover all of the weak parts, and prove them OK, or
vulerenable?

Is it all worth it? That would be a question you would have to answer.

Perhaps another valid approach would be to contact groups that have flown
gasohol, or pure ethanol airplanes. The EAA has done it; are there other
groups that have? Would they be willing to share what they have learned?

I await everyone's opinions. I agree with the premise that I think Dan has;
that it should be possible, and practical to develop a gasohol safe
airplane. "Some will no doubt shout, you will crash and burn!"

This could be an interesting discussion.
--
Jim in NC

"Dan Youngquist" wrote in message
hell.org...
On Tue, 5 Jun 2007, Morgans wrote:

I did think I understood that the problem with gasohol for airplanes was incompatibility with some rubber parts of
the fuel system.

That's what I've always heard too, but I've never been able to get anyone to back it up with info about SPECIFIC parts
that are in danger. In particular, I'd really like to know what SPECIFIC parts I have to change in my IO-360-A1A's
fuel system so I don't have to worry about alcohol. (It's in an experimental, so legality isn't an issue.) At the
same time, I see all manner of decades-old cars & trucks running for many years on gas that's part alcohol, with all
original fuel system parts, with no ill effects whatsoever. So I'm pretty close to writing off the whole ethanol fuel
system damage thing as an old wives' tale, but not yet willing to bet the farm on it.

-Dan

Fuel tank sealer (aka Proseal), fuel hoses, tank floats, carb floats, etc.