17prospective buyer

Interesting. I remember reading in my 87 S4 owners manual that using "gasohol" up to 10% was permitted but not recommended for long term use or something along those lines.

Eplebnista

To coin a phrase, more fuel to the fire:

http://www.crcao.com/reports/recents...l%20Report.pdf

This study found E15 can cause damage to valve seats in some engines. AAA used this study as the basis for a recommendation that drivers with older vehicles not use E15.....

BC

Valve Seats? How is 5% more ethanol (when E10 is fine) going to affect the metal in a valve seat?

How many miles is 500 hours? An average of some sort?

I'm reading to find out WHAT car of WHAT year the tests were run on. Without that, this is meaningless.

So the crap, poorly designed engines fail on E15 and E20, and the good ones don't, but the report finds that E15 and E20 are bad. Useless drivel.

depami

And by the way, don't set your battery on concrete. It will drain it. .

RKD in OKC

In 1986 I drove a 1976 914. It was a fuel injected 2 liter. Had been running Texaco gas in it . 2 months after Texaco started putting alchol in their gas, sold as gasohol, I had to replace all 4 injectors. The seals were leaking. Mechanic said to stop running that alcohol gas. A year later, about 6 months after I had sold the 914 it burned to the ground from a fuel leak. The guy that bought it drove it for a week, "Smelling gas!"

in 1994 I had an old worn out Stihl commercial line trimmer (weed eater). It's compression was about gone and it barely ran. Figured the 15 yo motor was toast I put some of my model airplane glow fuel in it, 10% nitro methane with oil pre-mixed. It ran GREAT! Had more power than it ever did. No problems for 4 years on that stuff. Only problem 10% Nitromethane was $9.00 a gallon back then.

Sold the old Stihl and got a new Stihl that ran on much cheaper gasoline. Basically because I had gotten out of RC planes and felt kinda funny going to the hobby shop to buy a gallon of glow fuel just for my weed eater.

Imo000

I think the nitro fuel, up here, is around $40/gallon.

joehelendetroit

How does one know if they are being sold E10 or E15? I have never seen any signage of pumps other than the generic disclaimer that the fuel may contain alcohol.

hb253

It depends on state regulations. For example, NJ has no requirement at all, so you have no idea if the gasoline you are buying has ethanol. Pennsylvania, on the other hand, requires a label on the gas pump. I drove through PA this past weekend and the pumps had labels stating "may contain up to 10% ethanol".

tveltman

since the manufacturer (Porsche) recommended 91 or higher, and specifically states that >10% EtOH to be a bad thing, go with 91 non ethanol. Unless your engine is set up for it (i.e. timing and compression ratio), you won't get any benefit from exceeding the octane content on your gasoline (assuming, of course, that the gas supplier is actually selling you 91 vs 89, but that is a different issue altogether).



To avoid the ensuing wall-o'-text, read the following TL,DR excerpt:

The manufacturer says not to use >10% ethanol for a reason, but fails to specify what that reason(s) is(are). You are assuming that because some fuel lines fail, this is why you shouldn't use it. I suspect the reality is vastly more complex.

Okay, now the wall-o'-text for those so inclined:

Corrosion is an extremely complicated process, as is rubber deterioration. Gasoline is not one compound, but a complex mixture of many different components. I agree that water is probably the culprit with respect to corrosion, but I think you will find that ethanol can be corrosive to certain metals (i.e. aluminum) under the right conditions. Any time two dissimilar metals are in contact with one another, adding water will make them corrode. Adding more EtOH will result in more water, and so corrosion may happen faster.

Just because something doesn't break when soaked in room temperature ethanol doesn't mean it won't fail under repetitive pressure and thermal cycling, as you would expect to see in an actual engine bay where fuel is being pumped through the lines heated by the waste heat from the engine. I am not doubting the words of those who have done the experiment, only pointing out that the experiments are one small part of the puzzle.

Another thing to consider is that combustion processes inside the engine can and will lead to incompletely combusted products that are acidic in nature (I'll skip the chemistry lesson). These then get entrained into the oil, where the additives in the oil to prevent acidification chew it up to protect the engine. If you have a significantly larger fraction of ethanol, then your oil may go acidic before the anticipated service interval, because the manufacturer did not account for the added acidity (and plans on a certain oil specification). If you are like some on this board, and check your oil via analysis, then perhaps you are safe. Also, perhaps it doesn't matter. I am a chemist, not a petroleum engineer/combustion scientist, but I think what I have said above is a well-reasoned position based on things that I know to be fact (and are relatively easily verifiable). If your oil is acidic, you will experience accelerated wear on bearing surfaces and other internal engine components. In my book, the engine dying is a significantly worse problem than a fuel line breaking, and I have been one of the unfortunate few who have had a shark combust from the dreaded fuel line break. Replacing fuel lines regularly is cheap and easy. Replacing engines regularly is neither.

Fabio421

For all of you guys looking for real world experience. There are quite a few 951 owners who have been using E85 for years without issues. The 951's of similar vintage as our 928's do not exhibit any of these harmfull effects that you guys are worried about. Please keep in mind that I'm only mentioning this to counter all of your wear releated questions. These cars have the AFR and timing adjusted for use with the E85. https://rennlist.com/forums/944-turb...ga-thread.html

BC

Just to be factual and clear - ethanol is in no way corrosive. Corrosive is "To Cause Corrosion" What is does is carry entrained water.

So water will do what? Allow steel to rust. What does it to to aluminum? Nothing.

If anything, the issue with aluminum and ethanol is that ethanol does not allow aluminum to create its oxide protective later, and therefore may start to appear white and powdery on the surface. This is aluminum's way of rusting. Ethanol aware people have, as best practices, suggested anodizing aluminum or nickel coating it.

Rubber? Well, 20 year old rubber causes its own issues. I have run two separate 928s on e85 for over 15k miles on each (all the way back to 2008) and the problems are (I replace the rubber fuel lines with flouro-based lines available from many places)

1) I have to make it richer, as it will run lean on normal injectors.
2) Stock Fuel pumps don't like getting hit late in life with the e85. The varnish that gets cleaned out of older systems seems to be a problem, and maybe the age of the fuel pump itself. A new pump lasts the whole project when I replace it after the first few 1000 miles.

The plastic tank is unaffected.
The injectors are unaffected, but I usually have to replace the filter baskets after a 1000 miles or so.
The fuel rails are unaffected.

The ports are spotless, the valves look new, and the piston tops get cleaned.

V8 Supercars from Australia use E85 I believe. Maybe they have more knowledge. But it works, its a GREAT fuel, makes great power, and is very flexible. All the way from 17:1 AFR for cruise and low-mid throttle, to 10:1 AFR for fat-rich power. (Petrol scale)

depami

And where are you getting these "facts"?

And why did all the NEW rubber in the snow blower carb kit turn hard and brittle after only one year of exposure to E10?

BC

Facts that old rubber is bad? Common Sense.

"New" rubber will not work if it is not viton, Flouro-based, or Synthetic rubber.

depami

And finally, there we have it.

E10 will cause problems when introduced into a system that has not been specifically prepared for it.

depami

How about additives?

What are does, don’ts and gotchas of additives for E-fuels vs. non-E-fuels?

http://www.goldeagle.com/brands/stabil/products.aspx
http://www.seafoamsales.com/
http://www.stp.com/products/