aluminium vs ethanol

[flyguy]

Just finished a test by immersing a test piece of aluminium in some of our fine California 5% ethanol auto gas. Left it there for 2 months. There were some very fine white spots spread around the surface, just barely visible. About like you would expect if left exposed to air. May have been on original sample, have to check source lot. Pretty much zip damage. Sanded off one side to remove any posssible protective cladding. Put back in for another month. Three months total. No additional corrosion on unsanded side. Zero corrosion on "exposed" sanded side.

So much for that little tidbit of generic knowledge.

Think I will do hoses next.

DC

[Len Petterson]

Re: aluminium vs ethanol

It is well know what alcohol will mix with water and the alcohol/water mixture relises oxygen, hence aluminium will corrode fast in what enviroment.
Hoses: In hydrualics ( I spend 20 years in the trade) A rubbercompond is ALLWAYS AFFECTED BY THE FLUID, any harm many not happen, but add a second type of fluid ( or mixture) watch out.
By changing fluid I have seen the rubber turn to "snott", a slippery slimmy mass! On my Taylorcraft I have had a hose swell internaly to a redused ID so the engine did NOT take the trottlle and did not develop full power, as it was affected by ETHANOL in the fuel. I check my hoses every annual as I run mogas, very good stuff,but! I test for ethanol But!
Len

[astjp2]

Re: aluminium vs ethanol

If you are not testing IAW one of the several ASTM specs, you are wasting your time and ours by even bringing it up!

[perryv1]

Re: aluminium vs ethanol

He is not wasting My time

[Hank Jarrett]

Re: aluminium vs ethanol

I think this is a case of the web being weak on showing the real intent of a statement. It sounded like a put down and probably wasn't intended to.
I have spent a lot of my career doing testing. Doing it to an accepted, repeatable standard gives the best and most useful results, BUT, there were a lot of times when we tossed something in a Mayonnaise jar and did a back of the file cabinet test. It at least tells you if it is worth doing a detailed test to more rigid standards.
Different types of aluminum, different water contents and different kinds of alcohol can all have an impact. I would say there was good reason to do more tests if I took some gasohol from a pump, tossed in a piece of aluminum flashing, and the aluminum was full of holes the next day. By the same token, I wouldn't think I was safe just because one test piece didn't start to corrode. Too many variables.
Sure helps get some funding for a good test when you come in to the bosses office and set a corroded hunk of aluminum on his desk from a test that didn't cost him anything (and yes, he probably WILL say the test doesn't prove anything. On the other side, it WILL probably get you some test money).
Hank

[Jim Herpst]

Re: aluminium vs ethanol

Flyguy. Thank you I learned something from your post. Opinions are just that. YOU my friend posted something of value. To the rude naysayers....The land is flat was easy to follow once apon a time also

Thanks for taking the time to provide a little research. Have not seen many cars on the side of the road lately because of this gas (guess the aluminum AND HOSES in cars is a different brand than the aircraft stuff. ) HMM PERHAPS WE OUGHT TO USE THESE ???

Now before everyone goes balistic. I AM NOT advocating the use of ALCOHOL in aircraft. I AM suggestingthat open minds should prevail. The draw backs are obvious. Having said this its not unsurmountable that it COULD POSSIBLY be used safely... I AM NOT ADVOCATING THIS no flames !!

[Marv]

Re: aluminium vs ethanol

Most cars today has gas tanks that i beleive is neopreme or plastic. at least that is what they apear to be and so is some of the fuel lines. Marv

[gcgilpin]

Re: aluminium vs ethanol

Lemming --- frequently-used metaphor in reference to people who go along unquestioningly with popular opinion.

[flyguy]

Re: aluminium vs ethanol

In checking my Aircraft Spruce catalog I see that about 2/3rds of the hoses are listed as being resistant to alcohol. Interesting. I did an internet search and found that there are a lot more types of synthetic "rubber" than I would have imagined.
Am working on getting some representitive hose samples. Have just one from a friend's RV4. Looks like a good hi-quality sample.

Think I will try an experiment exposing Cal. ethanol-laced fuel to moisture with aluminium samples. See what happens under that condition.

DC

[Rick Hadley]

Re: aluminium vs ethanol

[QUOTE=flyguy;
Think I will try an experiment exposing Cal. ethanol-laced fuel to moisture with aluminium samples. See what happens under that condition.

DC[/QUOTE]

That would be interesting. There are a lot of anecdotal horror stories about ethanol out there, but we've had it here in Iowa for over 25 years and I've used it in everything from Volkswagens to Cadillacs, even my 1952 (30s technology) Ford 8N tractor, with zero problems.

[Larry Lyons]

Re: aluminium vs ethanol

I too have been using it for a long time (automotive) with zero problems. In the late 70's and early 80's I used it in a 1967 Olds that would ping with low grade stuff, the ethanol was far cheaper and worked great! Better starting and more power too. Larry

[astjp2]

Re: aluminium vs ethanol

Have any of you looked for the ASTM tests? Testing fuels for corrision properties should not be treated like alchemy. Tim