Spring is getting ready to start on March 21st and it won't be long after that we will start breaking out the boats and the spring/summer equipment. A big topic of concern this year is anticipated to be the search for ethanol free fuel.Last year, the Bell Performance blog brought you warnings about how people across the nation were reporting problems of mysterious thick brown gel or brown sludge gumming up their engines and injectors, resulting in expensive repairs. What's been realized is that this brown gel forms when ethanol gas gets mixed with gas without ethanol that might have MTBE in it. The ethanol reacts with the MTBE and forms the thick gel and problems ensue.
Beyond the chemical formation of this problem-causing sludge, there's another reason to be more aware about mixing ethanol and pure gas - the water problem.
By now, everyone should know that ethanol gas attracts water. If you get more than 0.5% (2-3 teaspoons per gallon) of water in the fuel, the ethanol starts to separate out from the gasoline in a process called Phase Separation. When this happens, the fuel loses octane value and quality, and it's generally bad news.
Combining gas containing MTBE with ethanol-gas makes this problem worse. This is because MTBE itself has a lower ability to absorb and attract water than ethanol does. In practice this means it makes the new fuel blend less able to absorb water and more likely to break out with less water absorbed. And this means serious destruction of fuel quality actually happens sooner if you've happened to allow these two kinds of fuels to mix.
Just another reason to be more careful if you have a boat or other off-road engine using gasoline. You can save yourself a lot of headache, expense and time by doing so.
This post was published on March 17, 2012 and was updated on December 3, 2013.