Ethanol in Fuel

[turboplanner]

Found a few interesting threads:

 

http://saturdaymechanic.com/ethanol-issues-varnish-vs-gum-and-using-the-right-additive/

 

http://www.toledoblade.com/Energy/2011/07/12/Engine-issues-nag-boaters.html

 

http://www.crisfield.com/gold/Ethanol%20web%20ready.pdf

 

http://www.nbcnews.com/id/25936782/ns/business-consumer_news/t/mechanics-see-ethanol-damaging-small-engines/#.VIsyJiuUfz4

 

 

[kaz3g]

I saw the innards of a carburettor removed from a C65 in a Luscombe that had a a thick, white deposit over all of the interior. The aircraft had not been run for a few years and mogas was the fuel.

 

So I stick with Avgas despite the ridiculous price.

 

Kaz

 

 

[facthunter]

I've seen Gum deposits years ago in Cropduster RADIALS. Long before the ethanol possibility happened. There have been concerns on various brew in Mogas on and off for years. At the moment most of the old vehicles I am in touch with go reasonably well, but require a bit more choke cold on the current Mogas. Mixed two stroke I wouldn't keep long. For racing two strokes it has been mix fresh recommended all the time.. I have fuel going stale in unused vehicles all the time and it actually stinks. On higher performance aircraft engines(Turbo) and hot runners like a Jabiru, I would be wary of the octane ratings with mogas and there is always the possibility of it having unauthorised additives if not procured from a trustworthy source. Some fuel additives in current fuels definitely soften tank liner materials and I would worry about fibreglass tanks. Ethanol is hygroscopic (absorbs water) which may help until the fuel evaporates leaving the water.. Methanol and ethanol corrode some zinc/aluminium alloys. so running the fuel out or draining the carb would be useful. Nev

 

Nev

 

 

[turboplanner]

The first link compared varnish with the older fuels, and gum with enthanol. What I've seen looks like translucent gum in the carby.

 

Any ideas what the gum in the radials was from? did you ever find a way to clear it out?

 

It looks to me at the moment, from what I've read, that once you get the deposits from ethanol, you're in for trouble again and again and again, particularly in the drilled carby air galleries we've never had to unclog before. Compressed air won't clean it out and even boiling the carby in water for 15 minutes doesn't clean it out, although it does remove some.

 

 

[SDQDI]

Just recently (in the last three months or so) our local servo has changed from only stocking 95octane premium to only stocking 98 and already I've noticed the change. Just about a week or so ago I HAD to take the hornet out for a fly (hadn't flown for approximately 13 days) and in my preflight I noticed a horizontal in line glass filter had a very healthy blob of gummy goo in it. I have never had any hassles when using the 95. I wouldn't have thought it to be ethanol related though?

 

I was surprised at it happening that quick but I guess the 98 with its additives must evaporate quicker leaving this residue?

 

 

[rankamateur]

The last link looks more like it is pushing from a food production ethics point of view, interviewing mechanic only to push the point that food grade corn should not be being made into fuel. There is a lot of lobbying goes on around the edges of agriculture, always look a little deeper at what you read and smell the agenda.

 

 

[facthunter]

Turbo Back then,( late 90's )there was no ethanol. We were in the lead free with horrible cyclic hydrocarbons trying to get high octane. Seems they would be bad for you and the engine. To clean the engine strip and chemical bath and rebuild. I have never run a GA motor on anything but Avgas. I have had lead problems with plug fouling. I adopted the technique of taxiing with the mixture LEAN so lean that if I forgot it, it would cut out if I advanced the throttle, so NO chance of doing the take-off lean..

 

The speed way bikes I have run on straight Methanol. Some croppys in Brazil run on straight methanol too. I always TRY to drain the carbs after a run. White powdery corrosion forms and in some of the passages in the carb you would have difficulty cleaning them out.

 

There could be a reaction between any of the components in the terrible shandy we get for petrol if we let it age. Vev would be the best to comment on this, but if someone reckons the fuel EATS valves or chews up spark plugs, I give that particular expert a miss. Nev

 

 

[Oscar]

The BP Avgas contamination of quite a few years back now cost GA millions of $$ to rectify.

 

A very good friend of mine used to be the production manager at the Shell Clyde refinery; gave me the skinny on the industry. It's a long, involved and dirty story; suffice it to say, that the company logos on the bowsers have absolutely NO 1:1 relationship to the liquid that comes out of the nozzle. Next door to the Shell Clyde refinery, was the Caltex main depot for Sydney; there was a damn pipeline from the Shell tanks under the fence to the Caltex tanks. Shell tankers left the Shell refinery full of Shell refined petrol; Caltex tankers left the Caltex depot full of Shell refined petrol. The only difference was the paint on the trucks.

 

Mogas is hugely variable in quality at the bowser. With full engine monitoring and alert engine management plus intelligent fuel purchase and use / storage strategies, it can be a good source of energy for propulsive purposes; however if it is used without good knowledge of the 'issues' that can arise, it can be the mechanical equivalent of taking medication from unlabelled bottles on the basis of the colour of the pills inside.

 

 

[facthunter]

I thought it was Mobil but it really doesn't matter. The quality control process broke down and the Avgas ended up with Caustic in it, causing horrible corrosion to fuel system components of avgas powered aircraft. Many could not be economically repaired.

 

Selling the same fuel across brand names has been happening for years. The basic product meets a standard (we hope) but anyone can add things to it and the motivation to do it is to avoid excise charges. applied to solvents used in road transport fuels.Maybe some particular company additives were added to the base fuel. Some were supposed to be "final filtered" and some had Tigers in the tank. We used to refine most of our fuel used here back then but the % refined continues to dwindle. We hold about only 3 weeks of fuel in reserve here, about the lowest % of any comparable society. Clever country????. I'd hate to live in dopey one IF we are clever. Nev

 

 

[fly_tornado]

So will the current trend of fuel coming from Singapore fix the variability problem? These are the latest and greatest technology versus the 1970s technology in Australia.

 

 

[fly_tornado]

pump gas prices in the US just dropped below $2 a gallon

 

 

[Oscar]

I thought it was Mobil but it really doesn't matter. The quality control process broke down and the Avgas ended up with Caustic in it, causing horrible corrosion to fuel system components of avgas powered aircraft. Many could not be economically repaired.Selling the same fuel across brand names has been happening for years. The basic product meets a standard (we hope) but anyone can add things to it and the motivation to do it is to avoid excise charges. applied to solvents used in road transport fuels.Maybe some particular company additives were added to the base fuel. Some were supposed to be "final filtered" and some had Tigers in the tank. We used to refine most of our fuel used here back then but the % refined continues to dwindle. We hold about only 3 weeks of fuel in reserve here, about the lowest % of any comparable society. Clever country????. I'd hate to live in dopey one IF we are clever. Nev

Nev, you are correct, it was the stuff from the Mobil refinery at Altona.

 

 

[Guest ozzie]

Living in northern Queensland at the time. Some aircraft owners made a killing by leasing there aircraft to operators down south while their own aircraft were sorted out.

 

The gummy problem in radials may go back to the days when the majority of supercharged radials used purple avgas 145 or 160 i think it was. That stuff made the ol coupe bark.

 

 

[Downunder]

It looks to me at the moment, from what I've read, that once you get the deposits from ethanol, you're in for trouble again and again and again, particularly in the drilled carby air galleries we've never had to unclog before. Compressed air won't clean it out and even boiling the carby in water for 15 minutes doesn't clean it out, although it does remove some.

Have you tried the "crockpot method" (slow cooker and engine coolant/antifreeze) to clean the carbies?

Popular with some RC'ers for cleaning engines but not tried it myself. Suposed to work very well.

 

 

[facthunter]

)No ozzie It was mogas. The 130/145 was for the DC6's( R-2800 s etc They never had a particular problem with that fuel. Nev

 

 

[turboplanner]

http://www.bgprod.com.au/in-the-media/ethanol-madness/

[rankamateur]

http://www.bgprod.com.au/in-the-media/ethanol-madness/

I doubt any fuel injection system could inject enough water to cause hydrolock in the engine, who writes this stuff? There are agendas being pushed here that have little to do with engine performance.

 

 

[facthunter]

Some of the statements are a bit over the top> You can pour an awful lot of water into a motor running at high power and it won't stop it. It usually decarbonises it. Plenty of engines use water methanol injection. The FW 190 was one. DON"T try it on your motor though. It needs to be set up properly. Nev

 

 

[Guest ozzie]

Many high performance WW2 aircraft used water methanol injection for two reasons extra power for climb and altitude and better cooling.

 

 

[nomadpete]

I found (to my cost) that ethanol in e10 dissolved pinholes in my Lightwing fuel tanks.

 

There is a Good article in boatus website - (link is in my post under Lightwing threads) describes some research into the process. Note the main problem was associated with polyester resin but they also did a test on 'ethanol resistant'epoxy and found it lost tensile strength after a month or so of exposure to E10.

 

In summary, they say the ethanol molecules penetrate the resins and collect styrene, which is then in solution- so straight through filters, into engine, not burnt properly, deposits black gunk on exhaust valves until stems jam, and engine stops.

 

 

[Old Koreelah]

... Plenty of engines use water methanol injection. The FW 190 was one. DON"T try it on your motor though. It needs to be set up properly. Nev

...and Mitsubishi used it on later models of the A6M.

 

 

[Old Koreelah]

I found (to my cost) that ethanol in e10 dissolved pinholes in my Lightwing fuel tanks.There is a Good article in boatus website - (link is in my post under Lightwing threads) describes some research into the process. Note the main problem was associated with polyester resin but they also did a test on 'ethanol resistant'epoxy and found it lost tensile strength after a month or so of exposure to E10.

In summary, they say the ethanol molecules penetrate the resins and collect styrene, which is then in solution- so straight through filters, into engine, not burnt properly, deposits black gunk on exhaust valves until stems jam, and engine stops.

The chemical experts recommend Vinyl Ester for fuel tanks.

 

 

[robinsm]

why are you not testing the fuel before you put it in your tanks. Self preservation my friends. Ethanol in fuel may be ok if your tanks are made of vinyl ester resins but what is it doing to your fuel lines and carbies? Simple test to see if ethanol is present. Been doing it for years every time I buy fuel from the gas station. I use 98 fuel in the aircraft. Any ethanol would degrade the octane rating.

 

 

[facthunter]

Why do you say ethanol would degrade the octane rating of 98?. I'm not promoting its use but the octane rating of ethanol would be way above a figure of 98 .

 

Straight alcohol fuels run compression ratios higher than a hydrocarbon, even benzene C6H6 as far as I can recall. Nev

 

 

[Guest ozzie]

Just ethanol proof your fuel system. Be a good bit of insurance in case some is slipped in when you not looking.