By on March 7, 2011

Germany is in an uproar against ethanol. Last week, motorists celebrated a win against alcohol in their gasoline: Oil companies stopped the build-out of E10 gas stations. The matter still fuels the headlines. Over the weekend, German’s Die Welt newspaper shocked its readers with the news that the bio-benzene can ruin engines which supposedly are ok for the fuel.

“E10 is under suspicion to stress the engine oil harder than conventional fuel. This causes minimized viscosity and increased engine wear,” writes the paper. Supposedly, the stuff literally waters down the oil. Die Welt quotes Thomas Brüner of BMW who said: “The 10 percent ethanol increase the water in the engine. The water condenses and mixes with the oil. The oil gets diluted and ages faster.”

Ever since these news hit, you see more and more motorists checking their oil. Not for a lack of level, but for an increase. If the level rises, it’s caused by the ethanol water.  At the same time, the level of confusion is on the rise, and E10 sits unsold in full tanks.

Sunday evening. BMW sent out a press release in which the Munich car company  “supports the introduction of E10  in Germany.  The statements of Mr. Brüner do not refer to countries with a fuel quality as in the EU, they referred to countries with a lesser quality of fuel. Some older BMW vehicles require the anti-knock properties of Super Plus ROZ 98.”

Maybe you want to keep an eye on that dipstick.

PS: BMW today issued a flurry of press releases on this topic. In its third sixth missive (so far) (I get them in German and English, English version follows) BMW “would like to make the following clear:

  1. The condensation effect is a side effect of the normal combustion process – independently of the use of E10 – and therefore does not pose a problem.
  2. The oil-change intervals defined by BMW are not affected and therefore remain unchanged.
  3. The report’s falsely claimed link between the use of E10 fuel and “more rapid engine wear” does not exist.”
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34 Comments on “Killer Ethanol Continues To Confuse German Car Owners...”

  • avatar

    Could someone explain how this happens? Is it that the water in the ethanol doesn’t get burned or exhausted from the cylinder, and so ends up accumulating in the engine?
    I’m not apologizing for ethanol, by the way, I’m simply trying to understand how this accumulation of water in the oil pan could happen.

    • 0 avatar

      In Brazil we use hydrated alcohol (in other words, the ethanol comes with water. In America it’s anhydrous alcohol – without water). What that means is that in BRazilian cars they use water resistant materials anywhere the fuel runs. And water is expelled via exhaust. Evven though our alcohol comes with water, never heard of it acumulating in engine.

  • avatar

    Thomas Brüner of BMW who said: “The 10 percent ethanol increase the water in the engine. The water condenses and mixes with the oil. The oil gets diluted and ages faster.”
    Herr Brüner’s statement is the first that I’ve heard of this phenomenon being attributed to Ethanol.
    Condensed water vapor is produced by the combustion of hydrocarbons to include gasoline, especially while the engine cold.
    My guess is Herr Brüner is claiming that ethanol increases the rate of water vapor contamination.

    • 0 avatar

      Let me add that humid air at sea level in the summer contains about 3% water vapor by mass.  H20 is present even before hydrogen atoms are combined with oxygen during combustion.
      Winter air up in the Rockies may only be 1/2 of a percent by mass on a 32 degree F day.

  • avatar

    Ethanol is also very hygroscopic, i.e. it attracts water.

  • avatar

    I think ethanol from corn is a subsidized scam. Ethanol form sugar cane is another story as it is more efficient to prioduce. How do the Brazilians deal with ethanol as fuel for  their cars?  Do they see major engine war and tear?

    • 0 avatar

      I think ethanol from corn is a subsidized scam
      I think so, too. So is the alcohol program in BRazil (from sugarcane). What bothers me here is that I can’t get pure gasoline. Brazilian gasoline has a content of anything betwee 22 and 27% hyydrated alcohol (with a legal tolerance of 2% – so anywhere between 20 and 29 % of what you put in your tank when you use gasoline is alcohol). This means, as a rule of thumb, your car will get 70% of the mileage you would get when you run on Brazilian gasoline, when you run 100% alcohol. If it were real gasoline a full tank of alcohol will get you only 60% of the distance. Now, as a rule of thumb, too, the program is economically viable whenever the price of gasoline is above 30 or 40 USD (depends on who you ask).

      Now, most new cars in Brazil have what are called flex fuel engines. They can run or not the full gamut of variations. For some reason, only Renault claims its engines can run from 100% gasoline to 100% ethanol or any mixture in between. All other makers claim their engines are good to run from E20 (Brazilian gas) to E100. This is largely due to eletronic controls. The electronics are able to delay or anticipate the ignition point and thus avoid knocking. However, the flex part is a  bit of a misnomer as to be really flex, the engine should be able to change its compression ratio. Alcohol engines benefit from a much higher compression ratios. Which means all modern flex engines are compromises. It doesn’t run as well as it could on either fuel. SO it wastes both fuels. But it attends the political agenda.

      Older cars in Brazil suffer. But eventuallly all theparts that wear because of the water in the gasoline, wear out. As the mechanic puts in the new parts, these are made up to current standards. So eventually the car runs well enough on the current gasoline. However, it never runs as well as it could since the compression ratio of the original gasoline-only engine remains unchanged. Also, as the alcohol content in the gasoline varies (and vary it does, depending on the “needs” of those who can influence the program – namely, but not only, the farmers). So if the content was 25% for a while, then it goes up or down, the owner of the older car will have to take it to the mechanic for some fine tuning. In newer engines the electronics do it “automatically” (I wrote automatically between quotation marks as not all systems are the same. SOme have better capacity to adpt than others, probably due to greater calculating power in the system. Anecdotedly, Fiat’s system and Ford’s are the best, GM’s and VW’s are slow learners. The French are average, and surprisingly (or not as their experience is limited) the Japanese makers systems are only better than GM’s or VW’s).

      As to wear, well it’s controversial. Some say those engines that run only on alcohol run cleaner. Sludge is not something common in engines on alcohol. Now due to the higher stress they operate under (gasoline apparently is better at “greasing” the system and thus helping the oil), you would expect an engine that runs only on ethanol to last 70 to 75% of what an engine that ran sludge-free would last (at least that’s the theory)… If you are running just 10% ethanol content, I’d expect that extra wear to be almost neglieageble.

      Now all of the above on Brazilian alcohol/ethanol! Which is hydrous. In America the ethanol doesn’t come with water. In Germany no idea. So, what I said above, may or may not apply in America. Could someone explain the difference and different consequences of alcohol/ethanol being hydrous or anhydrous.

  • avatar

    4 out every 10 rows of corn now grown in the United States are converted into ethanol and burned in engines.
    Burning food for fuel.
    The US corn crop is 333 million tons, so the Feds and the Environmentalists are causing the burning of 133 million tons of corn (40% of 333 million).  133 million tons is 266 billion pounds of corn being burned needlessly.

    Enough to feed 600 million people @ 450 pounds of corn per person per year. 450 pounds of corn gives you all of the calories you need to survive for a whole year.

    • 0 avatar

      fidel is going away soon. This situation may dramatically change as Cuba (almost naturally) comes under the sphere of American inlfuence again.

    • 0 avatar

      Doesnt the excess corn get dumped to protect pricing?
      Ethanol subsidies exist b/c the Iowa caucaus is early – nothing more and nothing less

    • 0 avatar

      I think ethanol is a huge scam too.

      However, just in the interest of The Truth, the corn used for ethanol is not food-grade corn. It may be livestock grain, tho and it almost certainly is using up resources that could be producing food.

      plus, if it really makes any sense, why would there be federal subsidy beyond the first few years of it’s transition to mass market?

  • avatar

    But the some of the world’s finest engine experts at the EPA say that not only is E10 is okay but E15 should work fine too…or maybe it’s the world’s finest politicians at the White House who say that…

  • avatar

    Good reason to stick with 3 month/3000 mile oil changes (contrary to BMW’s recommendations)!  Seriously though this sounds like a crock of feces.  I haven’t done the chemistry/math but I would bet that there is much more water vapor produced from the normal combustion of the fuel than from water absorbed by the ethanol.

  • avatar

    This doesn’t seem to make sense.  On the average commute, your oil gets warm enough to boil off any water. 

    There is an issue of corrosion with ethanol.  I’ve always heard that the domestic flex fuel vehicles run a different fuel pump, fuel lines, and injectors.  A lot less rubber, and a lot more stainless steel is used. 

  • avatar

    I’ll call it a crock that it does any harm to the engine. The little Suzuki 1.3L I just arrived to work in has driven 315,000 miles on it over the last 11 years. MN has had 10% ethanol in ALL it’s gas for over 20 years. This car has run nothing but, and had NEVER had an issue with it.

    • 0 avatar

      in IL we have been running on ethanol for a long time and now, we dont have a choice. Not a single ethanol-free pump in the Chicago area.

      Even if it doesnt do actual damage to cars, there is no question that it harms gas mileage.

      also, and i am not sure if this is accurate or not, but i’ve heard in a number of places that the energy used to produce ethanol is greater than the energy it provides. Does anyone know if this is true?

      • 0 avatar

        Even if it doesnt do actual damage to cars

        Modern cars are designed to run on E10. “Top tier” gas has to be E10. If you have a newer car, you should be putting E10 in it, since it is supposed to have it. (The ethanol has detergent value.)

        there is no question that it harms gas mileage.

        Ethanol has lower energy content than does gasoline, so the MPG declines a bit accordingly. (The loss should be about 3%.)

        But the car is using less gasoline, since 10% of the fuel isn't comprised of gasoline. The mileage obtained from the gasoline is the same. There is no loss.

        i’ve heard in a number of places that the energy used to produce ethanol is greater than the energy it provides. Does anyone know if this is true?

        No, it’s false. Ethanol produces distillers grains (animal feed) as a byproduct. On the whole, it’s energy positive. It’s energy negative if you ignore the byproducts, but there is no good reason to ignore the byproducts.

        That being said, corn is not the ideal crop for producing ethanol. And there is no way that we could ever produce enough biofuel of any kind to completely eliminate gasoline or diesel consumption. Biofuels are a supplement, not a replacement.

  • avatar

    I’ve been hating ethanol and thinking ill thoughts towards corn farmers since it was forced upon us hapless consumers in the USA some years ago. In my more modern cars with fuel injection, E10, means the car will get 10% fewer miles per gallon. They make us pay for this!? was my first reaction. Anything older than that and you’re in for real trouble. When I take my 1980 Cadillac out after the winter, the extreme amount of water that accumulated in the gas tank thanks to the ethanol combines with the fuel to create an incombustible combination of fuel and water that will make the eyes water of anyone standing next to it when I’m running it out. Then the oil needs to be changed, usually twice, to get the gasoline out of it.
    My 69 Continental is not as susceptible to the water that ethanol accumulates, but it kills the potency of the gasoline so that any acceleration near wide-open-throttle will cause the car to ping. Luckily, I have a source for 100LL, but it limits the distance I can go with the car, unless I want to turn a fine running machine into a wheezing, belching pig with E10.
    Like motorcycles? My father had a 1990 Buell with a hand laid fiberglass gas tank. After his first season with E10, the fuel had absorbed into the fiberglass of the tank and was lifting the paint off of the topside. It got to the point where he would drain the fuel out after each ride, but the tank had been ruined.
    Maybe over here, where gas is under $4.00 a gallon, most people can ignore the fact that we’ve been buying fuel of lower and lower quality. If I was paying double for it, I certainly wouldn’t want my fuel supply ruined by a bunch of do-gooders and goldbricking, subsidized farmers.

    • 0 avatar

      Ethanol has a lower energy density than gasoline, but it still has some energy; so no, your fuel economy won’t fall in direct proportion to the ethanol content.
      E10 has about 3% lower energy content per unit volume than pure gasoline, so at most I’d expect your fuel economy to drop 3% rather than 10%.
      In the last 5 years I’ve run vast quantities of E10 through cars from the 60’s, 70’s, 80’s 90’s, and 00’s and bikes from the 80’s, 90’s and 00’s and haven’t seen any of the problems you describe above.  I’m no fan of ethanol, but I don’t think it’s nearly the car-destroying boogeyman you guys make it out to be.

  • avatar

    Oh you’ve got to be kidding me. That’s a load of horse SH*t, and sounds like scare tactics by the oil companies and anti Ethanol groups. We’ve been running E10 in the US for years and have ran into NONE of these issues. Why is water going to suddenly start collecting in the oil of these German drivers engines when it isn’t happening over here?

    I’m running pure E85 in my 98 Civic (only added larger fuel injectors) and I have no issues whatsoever. It’s my 2nd year running it and one thing I’ll say I do notice with my oil, is that it stays much cleaner a lot longer. After 7500 miles it’s not black like it was on gas.

    Alcohol is a good fuel (it burns soo cleanly) it’s just how we make it that needs work.

  • avatar

    define “average commute”.
    Mine is 2.1 miles. I am fairly certain that the oil isn’t getting hot enough to boil off anything.
    The science still doesn’t make sense to me.  E10 means the ethanal is attracting the water; after all ethanal is just dry gas.  The oil may not get hot enough, but clearly in the combustion chamber the water is being turned into steam — which comes out the rear.

  • avatar
    Carlson Fan

    “Oh you’ve got to be kidding me. That’s a load of horse SH*t, and sounds like scare tactics by the oil companies and anti Ethanol groups. We’ve been running E10 in the US for years and have ran into NONE of these issues.”

    Exactly! The truth about ethanol(E10) issues is there are none. I pulled 5 gallons of 2+ year old E10 gas out of my wifes snowmobile that had gotten bad enough that it wouldn’t start. Before I dumped it into the gas tank of my GMC PU, I checked for water absorbtion and phase separation. Guess what, there wasn’t any. That truck ran just fine and that was 3 years ago so it obviously didn’t cause any problems. !  

    • 0 avatar

      Have you tried running some “E0” to compare to E10? I get better performance and 10% better mileage. I know the BTU difference is less than 10%, so I am not sure why this happens across multiple vehicles, but it’s real. As far as wear and tear, water in the oil, and so forth, I’m not seeing that. I am a little suspicious of increased fouling of valves and such, however.
      BTW – as far as water absorption and phase separation: You do know that ethanol and water are very compatible, right? The water issue folks keep alluding to is that ethanol absorbs water from the air and ‘pulls’ it into your fuel system. The water is kept well-dispersed by the ethanol, so you’re not going to see the phase separation you would have seen in Gramps’ Model A with old-fashioned non-polar E0 gasoline, but just the same you are likely to have plenty of water in your ‘gas’ doing whatever water does, including facilitating corrosion in non-flexfuel vehicles. This is the very reason ethanol has to be (energy-intensively) shipped around the country in separate tank cars and trucks, rather than blended into the gas in pipelines. OTOH, a little bit of water is not going to do too much to affect combustion, so not surprising your PU ran fine.

  • avatar

    The stuff is murder on boat engines. I have friend who needed to have his motor rebuild TWICE due to ethanol issues.
    As other stated it attracts WATER and guess what happens when the vehicle you putting the ethanol in spends its whole life in a very humid environment? Water in your gas! That water gets passed on to the engine (despite even the best filters) and that is when things take a turn for the worst. Not to mention the damage ethanol does to fuel lines and fuel tanks. The stuff is evil. In your car it might not be a big deal, but in boats and smaller 2-stroke engines (lawn mowers, chain saws, ATVs, bikes, etc) it does do damage.

    • 0 avatar

      So, what specific failures are caused by the use of fuel containing trace amounts of WATER?
      What parts of your friend’s boat engine failed, and how did you determine that it was due to ethanol?

  • avatar

    The only problem I’m aware of with E10 occurs in older cars with carburetors or the old Bosch CIS fuel injection.  The ethanol can dissolve the gunk in the bottom of the gas tank on old cars and it gets pumped through the fuel delivery system blocking various orfices.  I guess the newer electronic injection systems are not as sensitive.

    • 0 avatar

      I had E-10 ruin the float in the Solex carburetor in my ’66 Beetle twice in three years.  I also had a rubber fuel line connector go bad in those three years after a pan up restoration.  E-10 is bad stuff for old cars, which is why I’m out of the hobby now.

  • avatar
    Carlson Fan

    “The stuff is murder on boat engines. I have friend who needed to have his motor rebuild TWICE due to ethanol issues”

    BS. The motor failures have nothing to do w/ethanol.  I’ve been a boater my whole life and have been running E10 in my own boats for over 20 years. 

  • avatar

    I always thought BMWs were retaining water because owners weren’t revving them high enough to cook off moisture. Maybe the motors need to be designed for more leisurely driving styles.

  • avatar

    Only 10% of the corn crop in the US is sweet corn. The rest is feed corn, which is for animals and ethanol production. Once distilled, the remainder of the corn can be used as feed. How often that happens, I don’t know.

    Since 1986 in the US, cars have been required to be able to handle alcohol fuels, meaning the fuel system should be made of materials that will not degrade in the presence of alcohol. Additionally, a number of older carburetors usually have the option to get alcohol resistant parts, in the event a conversion is needed.

    Growing up in the midwest, the fastest race cars were on methanol, and they used off-the-shelf Holleys that were converted to methanol. They usually had viton needles, different floats, used larger jets than gasoline carburetors. I think the reason why we use anhydrous alcohol in the US is since alcohol is hygroscopic and gets water from the air, already having water in the alcohol lowers the efficiency of the blended fuel.

    I’ve seen studies (from Minnesota) claiming that E30 is actually a better fuel than E10, that the mileage doesn’t get any worse, but the amount of gasoline is less, naturally. A few years ago, Volvo and SAAB were both touting their E85 cars in Sweden, which were specifically set up to run on the fuel, with higher compression engines and retarded timing maps. Anytime a motor runs on both gasoline and ethanol, it will be set up to run on gasoline first, and ethanol second, which seems to ruin any benefit from using ethanol in the first place.
    Ideally, I’d like to see bio-butanol, as a replacement for both gasoline and ethanol. It has the long carbon chains like gasoline, but burns clean like alcohol. I know a company called Coskata was working with GM to increase methods of ethanol production, it’s a shame they weren’t working on butanol instead. They developed an anaerobic microbe that would emit ethanol from feedstocks that could be any kind of starchy substance. But, with genetic engineering methods, they may be able to. I don’t know what the reasoning was to concentrate on ethanol.
    I think the larger threat to the worlds corn production is the unstemmed proliferation of genetically modified strains that have gotten out into the ‘wild’. We really don’t know what will happen in the future with corn. Here’s hoping we can take our garbage out of the landfills and recycle it back into light crude.

  • avatar

    I just can’t understand why we use fuel that 1) adds cost to the gallon of gas 2) decreases mileage 3) is subsidized heavily by the government and 4) could damage engines.
    The Germans might be doing the typical German risk-averse thing with this stuff, but at the end of the day, if it works in getting rid of ethanol gas, then I’m all for trying it over here :)

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