Ethanol Blended Fuels
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Joined: Nov 2006
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2007 E63
Ethanol Blended Fuels
I have a friend who says that BMW told him not to run E10 fuel in his E60 M5. My local service advisor told me that it was OK to use E10 in my E63. Is E10 really bad for a high performance engine, such as E63 or M5? Is this a myth??
MBWorld Fanatic!
Joined: Jan 2004
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From: Salt Lake City (but not Morm)
2003 E55 & 2014 GL550
100% NO WAY.
Here is just a sample of the mighty E10 in powerboats.......
Many of these stations are selling Ethanol blended gasoline (E-10) and therein “lies the rub.” According to the experts, E-10 fuel is raising all kinds of problems with marine engines and some fuel tanks. First of all, as I understand it, Ethanol is a solvent and as such is dissolving the resin in some fiberglass fuel tanks, especially the ones made with polyester resin. In older boats, it will also dissolve any acumination of contaminates in the fuel tank and system and send the whole gooey mess through the system into the engine itself.
Most gasoline sold without Ethanol in it has a component called MBTE added to the base gasoline. Now if you mix Ethanol with MBTE, you create a gel-like substance that clogs up everything!
Wait, it gets even worse! Ethanol attracts water. Unlike cars, boat fuel tanks vent into the open air. Thus, Ethanol can literally suck moisture in from the air to collect in your fuel tank. For those of us that keep our boats in storage for 5 to 6 months (or more), the shelf life of E-10 is estimated to possibly be as short as 60 to 90 days before it starts to turn into “chewing gum”, so to speak.
For all of you boaters with high performance boats, here is some more disturbing news. When Ethanol mixes with water, it separates form the base gasoline product and can lower a 93 octane fuel to an 89 octane fuel in a jiffy. That fact alone could void the manufacturer’s warranty on a high performance engine.
Here is just a sample of the mighty E10 in powerboats.......
Many of these stations are selling Ethanol blended gasoline (E-10) and therein “lies the rub.” According to the experts, E-10 fuel is raising all kinds of problems with marine engines and some fuel tanks. First of all, as I understand it, Ethanol is a solvent and as such is dissolving the resin in some fiberglass fuel tanks, especially the ones made with polyester resin. In older boats, it will also dissolve any acumination of contaminates in the fuel tank and system and send the whole gooey mess through the system into the engine itself.
Most gasoline sold without Ethanol in it has a component called MBTE added to the base gasoline. Now if you mix Ethanol with MBTE, you create a gel-like substance that clogs up everything!
Wait, it gets even worse! Ethanol attracts water. Unlike cars, boat fuel tanks vent into the open air. Thus, Ethanol can literally suck moisture in from the air to collect in your fuel tank. For those of us that keep our boats in storage for 5 to 6 months (or more), the shelf life of E-10 is estimated to possibly be as short as 60 to 90 days before it starts to turn into “chewing gum”, so to speak.
For all of you boaters with high performance boats, here is some more disturbing news. When Ethanol mixes with water, it separates form the base gasoline product and can lower a 93 octane fuel to an 89 octane fuel in a jiffy. That fact alone could void the manufacturer’s warranty on a high performance engine.
Former Vendor of MBWorld
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From: In a box
W211 E55
I dare you to find gas without ethanol in certain markets requiring oxygenates (most major markets) 
It is a cheap oxygenator as well as octane modifier. Count your blessings if you don't have to run it, as ethanol contains less energy per mass unit than gasoline.
Most automotive apps have abandoned fiberglass as a tank medium long ago, but this could still apply for certain older models and kit-cars.
It is a cheap oxygenator as well as octane modifier. Count your blessings if you don't have to run it, as ethanol contains less energy per mass unit than gasoline.
Most automotive apps have abandoned fiberglass as a tank medium long ago, but this could still apply for certain older models and kit-cars.
Super Member
Joined: Aug 2005
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What? Ethanol and MTBE are both hydrocarbons, so there should be no compatibility issues. In fact, MTBE is produce from methanol. I think your source needs to do a little more research. There should be no issues with runniing E10 in any car produced during the past 25 years - BMW included.
