Gasahol Update

"RST Engineering" wrote in message

a.. What you say is true...as far as it goes. What the first paragraph
IMPLIES is that there IS a safe way to fly with alcohol between 1 and 5%.
In fact, they even give guidelines for it (use caution, 24 hours to use
it,
drain the system afterwards, etc.). If you don't want to do this, then DO
NOT FLY.

a.. Or am I reading it wrong?\

That is about as poorly worded as anything I haave ever seen. My take on it
is that you should not fly with up to 5%, but you don't have to do something
to the fuel system for up to 24 hours. If you have more than 5%, you have
to act immediately, and take extreme actions in protecting your fuel system,
or your plane is screwed.

But in the long run, the only one who knows for sure is the person that
wrote that piece of work.
--
Jim in NC

"Morgans" wrote in message
...

big snip

to the fuel system for up to 24 hours. If you have more than 5%, you have
to act immediately, and take extreme actions in protecting your fuel
system,
or your plane is screwed.

I'm missing something in this discussion. What does gasahol do to the
fuel system that is destructive? For that matter, what damage does it do to
the engine?

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.

"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).

"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.

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.

What does gasahol do to the
fuel system that is destructive?

Nobody has hard data. All fuel system tests have been with pure alcohol in
a lab beaker. Sort of like feeding rats 100% saccharin and then noting an
early rat demise.


For that matter, what damage does it do to
the engine?

None. As a matter of fact, it cleans the hell out of the upper end.



1) You will only get 95% of the engine's output power compared to pure
gasoline,

Yes, at 100% ethanol. What is the output power degradation at 5% ethanol
concentration? 0.05% or something like that.


2) Your fuel system elastomeric seals, diaphrams, floats etc are not
compatible with any substantial alcohol content,

Your source for the study and verifiable results, please?



3) The vapor pressure of the alcohol-laced fuel is higher,

Your source for the study and verifiable results, please?



4) The long term storage properties are horrible.

Certainly you must be kidding. I've got a bottle of Everclear that must be
30 years old and still has the same effect as the day I opened the bottle.
Alcohol has a MUCH better storage characteristic than gasoline.




Did I miss any?

Most all of them.


Jim

"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.