Miscellaneous Subjects

(Transcribed from R/C Report Issue 269 (December, 2008)

Author:  Brian O’Meara

Problems resulting from gasoline containing ethanol.

          No, this is not a soapbox sermon on why I think E-10 fuel (10% ethanol, 90% gasoline) is a colossally stupid (i.e. political) idea.  I’m only mentioning it here to alert modelers using gas engines to the problems cropping up all over the country.  According to several articles published in consumer and automotive magazines, E10 fuel cost more (tax dollars + pump price) and gives less mileage than pure gasoline.  That, however, is not the big problem to modelers.

          The corn-based ethanol now is widely included in pump gasoline is causing some fuel tubing (including Tygon®) to swell, much like silicone tubing does in gasoline.  This swelling is causing some in-tank fuel lines to loosen and fall off, usually leading to a dead engine.  The ethanol also attacks some rubber and plastic parts in carburetors, and eats away at fiberglass fuel tanks.  These problems are being noted in models as well as full sized aircraft, various gas engine yard tools, many boats and motorcycles, and some older vehicles.

          What can we do?  Most states require signs on gas pumps dispensing E10 (“Contains Ethanol”).  Look for the sign if you want to avoid E10, and then shop elsewhere.  If your state has no such law, and you may be buying E10 without knowing it, then you may have no alternative but to visit an automotive speed shop and buy pure racing gas.  Some people are switching to avgas (aviation gas).  I’ve seen one report that says avgas already contains ethanol, but I don’t think it does, and I spent over six hours one night researching the subject on the internet.  (Did you know that it costs so much to produce a gallon of ethanol, to make it affordable to the public our government is paying farmers to grow the corn they then sell to the refineries, and they pay the refineries to buy and use the alcohol which they sell to us?)  You and I are paying over a dollar a gallon in taxes (some reports say over $2.00 but I don’t know who to believe) for every gallon of ethanol produced, even before we buy it!

          I believe avgas is still alcohol-free.  The FAA currently prohibits its use in fiberglass fuel tanks, thus weakening the tank’s walls, the sludge produced can clog fuel filters and fuel metering jets, just as it’s already doing in many boats and motorcycles.

          How can you tell if gasoline has ethanol in it?  According to an email from Brian O’Meara, one of the nations more highly respected scale modelers, and owner of the oldest ford dealer in Colorado:  “We check the gas in Colorado by putting some gas in a small (clear glass) jar, and then add about an ounce or two of water.  If (the gas) has ethanol in it, the water will turn to gum balls.  Not much we can do about it, because it is almost impossible to find gas without the stuff.  My radial hates gas with ethanol.  And, yes, we have found that it swells Tygon®.