Gasahol Update

What does gasahol do to the
fuel system that is destructive? For that matter, what damage does it do to
the engine?

1) You will only get 95% of the engine's output power compared to pure
gasoline,
2) Your fuel system elastomeric seals, diaphrams, floats etc are not
compatible with any substantial alcohol content,
3) The vapor pressure of the alcohol-laced fuel is higher,
4) The long term storage properties are horrible.

Did I miss any?

nrp wrote:

1) You will only get 95% of the engine's output power compared to pure
gasoline,
2) Your fuel system elastomeric seals, diaphrams, floats etc are not
compatible with any substantial alcohol content,
3) The vapor pressure of the alcohol-laced fuel is higher,
4) The long term storage properties are horrible.

Did I miss any?


Something called "phase separation." At altitude, the gasoline and alcohol do
not remain mixed. To quote the EAA page, "Phase separation is the last reason,
which happens when the fuel is cooled as a result of the aircraft’s climbing to
higher altitude. When the alcohol separates from the gasoline, it may carry
water that has been held in solution and that cannot be handled by the sediment
bowl."

George Patterson
Why do men's hearts beat faster, knees get weak, throats become dry,
and they think irrationally when a woman wears leather clothing?
Because she smells like a new truck.

"George Patterson" wrote in message
news:AmPne.6366$zb.2080@trndny06...
Did I miss any?


Something called "phase separation." At altitude, the gasoline and alcohol
do not remain mixed. To quote the EAA page, "Phase separation is the last
reason, which happens when the fuel is cooled as a result of the aircraft’s
climbing to higher altitude. When the alcohol separates from the gasoline,
it may carry water that has been held in solution and that cannot be
handled by the sediment bowl."

George Patterson

With respect George, I totally agree with your statement but my
question was regarding what damage is caused by the alcohol, not its effect
on performance. I'd like to read the EAA reference, please give me the URL.

Casey Wilson wrote:

I'd like to read the EAA reference, please give me the URL.

Basic info is here http://www.eaa.org/education/fuel/oxygenated.html
This - http://www.eaa.org/education/fuel/knopp_alcohol.html is specific to
problems caused by alcohol.
This is the index to the EAA autofuel program information.
http://www.eaa.org/education/fuel/index.html

George Patterson
Why do men's hearts beat faster, knees get weak, throats become dry,
and they think irrationally when a woman wears leather clothing?
Because she smells like a new truck.

"George Patterson" wrote in message
news:LPQne.12848$zb.9296@trndny01...
Casey Wilson wrote:

I'd like to read the EAA reference, please give me the URL.

Basic info is here http://www.eaa.org/education/fuel/oxygenated.html
This - http://www.eaa.org/education/fuel/knopp_alcohol.html is specific to
problems caused by alcohol.
This is the index to the EAA autofuel program information.
http://www.eaa.org/education/fuel/index.html

George Patterson

Thanks George, I'll do some reading.

"nrp" wrote in message
ps.com...

What does gasahol do to the
fuel system that is destructive? For that matter, what damage does it do
to
the engine?

1) You will only get 95% of the engine's output power compared to pure
gasoline,
2) Your fuel system elastomeric seals, diaphrams, floats etc are not
compatible with any substantial alcohol content,
3) The vapor pressure of the alcohol-laced fuel is higher,
4) The long term storage properties are horrible.

Did I miss any?

Sort of..., #'s 1, 3, and 4 don't answer the questions. While #2 seems
to reply by alleging incompatibility, it doesn't state the damage. How are
those components not compatible? Do they explode?
Maybe you could direct me to a white paper that describes the problem
between elastomers and alcohol. So far, I've looked at four companies that
manufacture elastomeric seals and find nothing to uphold the claim of bad
chemical reeactions.
On the other hand, I find a couple of references dealing with problems
using elastomeric seals that have nothing to do with alcohol. Additionally,
I found more than one company (B.F. Goodrich, for one example) that
manufactures elastomeric products specifically for use with alcohol(s).

Casey Wilson wrote:

Sort of..., #'s 1, 3, and 4 don't answer the questions. While #2 seems
to reply by alleging incompatibility, it doesn't state the damage. How are
those components not compatible? Do they explode?

Problems vary depending on the composition of the items. Generally seals,
gaskets, and diaphrams *may* swell and/or soften when exposed to alcohol. This
caused problems with some automobiles when gasohol was introduced in the
mid-70s. I do not reliably remember what substances were most affected, but
manufacturers reacted by changing the composition of replacement items. Owners
reacted by refusing to buy gasohol. Nothing quite like having a diaphram type
fuel pump die or start pumping gas into the crankcase when you're on the road.

George Patterson
Why do men's hearts beat faster, knees get weak, throats become dry,
and they think irrationally when a woman wears leather clothing?
Because she smells like a new truck.

On Fri, 03 Jun 2005 04:27:28 GMT, George Patterson
wrote:

Casey Wilson wrote:

Sort of..., #'s 1, 3, and 4 don't answer the questions. While #2 seems
to reply by alleging incompatibility, it doesn't state the damage. How are
those components not compatible? Do they explode?

Problems vary depending on the composition of the items. Generally seals,
gaskets, and diaphrams *may* swell and/or soften when exposed to alcohol. This
caused problems with some automobiles when gasohol was introduced in the
mid-70s. I do not reliably remember what substances were most affected

Well I do, I was an auto mechanic with gas started being laced with
alcohol, and saw the results several times.

I'll never forget the first time we got a complaint. They guy had a
midsize Chrysler and brought it in complaining of it not running well.

We got it into the shop and popped the hood. It immediately drew a
crowd, every single mechanic was hanging over the engine compartment
with their mouth's dropped and their eyes wide open in amazement.
Every single hose connected to the fuel system, including vent hoses,
was swelled to twice or three times it's size and was sticky and gooey
to touch.

We realised that this was just the surface. Every diaphram in the
carburator, every rubber piece, would be the same way. The fuel line
from the tank had several hoses also, and they were all shot in the
same way.

And it smelled like alcohol.

It would likely take a mechanic several days to properly replace every
single component that had been affected, and at the time there were no
known compatible substitutes, although they showed up remarkably fast.

So "IF" your airplane does not have hoses compatible with alcohol, or
any component of your fuel system is not compatible with alcohol, this
is what you are facing.

Corky Scott

Corky Scott wrote:
On Fri, 03 Jun 2005 04:27:28 GMT, George Patterson
wrote:

Casey Wilson wrote:

Sort of..., #'s 1, 3, and 4 don't answer the questions. While #2 seems
to reply by alleging incompatibility, it doesn't state the damage. How are
those components not compatible? Do they explode?

Problems vary depending on the composition of the items. Generally seals,
gaskets, and diaphrams *may* swell and/or soften when exposed to alcohol. This
caused problems with some automobiles when gasohol was introduced in the
mid-70s. I do not reliably remember what substances were most affected

Well I do, I was an auto mechanic with gas started being laced with
alcohol, and saw the results several times.

I'll never forget the first time we got a complaint. They guy had a
midsize Chrysler and brought it in complaining of it not running well.

We got it into the shop and popped the hood. It immediately drew a
crowd, every single mechanic was hanging over the engine compartment
with their mouth's dropped and their eyes wide open in amazement.
Every single hose connected to the fuel system, including vent hoses,
was swelled to twice or three times it's size and was sticky and gooey
to touch.

We realised that this was just the surface. Every diaphram in the
carburator, every rubber piece, would be the same way. The fuel line
from the tank had several hoses also, and they were all shot in the
same way.

And it smelled like alcohol.

It would likely take a mechanic several days to properly replace every
single component that had been affected, and at the time there were no
known compatible substitutes, although they showed up remarkably fast.

So "IF" your airplane does not have hoses compatible with alcohol, or
any component of your fuel system is not compatible with alcohol, this
is what you are facing.

Corky Scott

Sounds like a problem with an additive to me. Some of the early octane
boosters were alcohol mixed with toulene and acetone. I think Wenn's
or STP or some company got a class action suit over this. BTW the
toulend in 100 LL melted the plastic floats put in a lot of planes made
for 80 avgas. You won't smell a small quantity pure ethanol or
methanol, they have very low oders, the alcohol in distilled liquors
smells because of the organic compounds from the fruit, grain, or maybe
the yeast, I cannot remember.

Sport Pilot wrote:

You won't smell a small quantity pure ethanol or
methanol, they have very low oders, the alcohol in distilled liquors
smells because of the organic compounds from the fruit, grain, or maybe
the yeast, I cannot remember.

First off, we're not talking about a small quantity here; we're talking about
nearly 10% of the fuel. That means several gallons, at a minimum, and that's
just for one tank of gas. Secondly, the alcohol used in the 70's was ethanol
made from corn; a distilled liquor. In essence, pure grain alcohol. It stinks
(as any old fratrat can tell you).

George Patterson
Why do men's hearts beat faster, knees get weak, throats become dry,
and they think irrationally when a woman wears leather clothing?
Because she smells like a new truck.