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AAA Warning on Ethanol

Components which were designed to survive for a reasonable period of time in E10 may fail sooner in E15.

Water absorption can occur before you pump a drop into your tank and no fuel system is isolated from the atmosphere. If it was, you'd have a vaccuum in your tank as soon as you started riding. Outside air filling the void in the tank as fuel is consumed may be filtered through a carbon canister, but that doesn't remove humidity.

If you have a fuel injected engine with a closed loop system that was designed to run on E10, it can probably accomodate E15 without too much trouble. If the design was marginal and you were maxing out the trim, fuel injector flow or pump capacity with E10, E15 may push you over the edge. Open loop and carbureted engines may require modification to run properly on E15. Unfortunately, those modifications may be illegal.

Fuel pumps, injectors and intake valves are lubricated by fuel. Ethanol provides less lubrication than other gasoline components and may reduce component life as the percentage is increased.

E15 isn't an absolute evil, but it will cause issues for some engines. Don't assume that if an engine was certified to run on E10 that it was optimized for it. It may have already been on the edge at 10% and 15% ethanol may push it over.

The traction this thread has shown may have as much to do with the amounts of ethanol going into us around this time of year as is going into our vehicles.

You're right, I mispoke. The fuel system is not airtight, but I stand by my claim (and you don't actually contradict it) that the amounts of water taken up by ethanol in our fuels under normal circumstances is insignificant. If someone makes the claim that ethanol in our fuel hurts longevity in any way I would ask to see some firm evidence beyond the anedotal. Ofcourse I'm speaking of post-ethanol era vehicles.

As for gasoline being a lubricant there may be additives in it that help lubricate some parts, but the question is whether the presence of ethanol at these relatively small amounts will degrade that. Hard to know at this point, but it obviously doesn't at 10% so how likely is it to happen at 15%.

If someones fuel system was already in marginal condition for whatever reason and it failed after a tankful of E15, you can be sure they'd probably blame the EPA. But would that blame be justified.

I'm in no way in favor of any ethanol in gasoline and even this small increase means my gasoline dollar goes from being worth 90 cents to being worth 85 cents. I just don't think it's likely to affect our vehicles as some have suggested.

And...oh yeah, I wouldn't put a whole lot of stock in anything the manufacturers say until they put it in enforceble (and challengeable) language in their warranties. I don't doubt for a minute that they are above using this issue as a way to avoid honoring defective fuel system warranty issues that have nothing whatever to do with ethanol.

Happy new year all.
 
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