Originally Posted by Hipster
+1 It's amazing the amount of residue Ethanol leaves behind.
Ethanol, dries clean. It's not ethanol that does that. It's something in the fuel or additives that does that, maybe because someone took the cheap option and used something that was not suitable. There are another 166 odd chemicals in what most people call "pure fuel".
Used to see that kind of thing a lot before ethanol was a twinkle in the polies eyes.
We cleaned it off and never went to that servo again. Well until we forgot or they changed hands or something.
Have a read http://en.wikipedia.org/wiki/Gasoline
and that is just the basics...