Posted by Don in Missouri [172.68.38.43] on Friday, May 05, 2017 at 13:29:16 :
In Reply to: Re: Ethanol-free Gas in Ft. Worth, TX Area posted by Johnd [162.158.78.25] on Friday, May 05, 2017 at 12:33:54 :
Aviation gas starts out with a much lower vapor pressure than gas for cars. All fuel will lose the light hydrocarbons that evaporate over time. Av gas starts out with more of them, so you can lose a lot and still have more than you started with in on-road fuel.
Tests show that on-road gasoline can lose enough light hydrocarbons through evaporation to fall out of spec in 3 months of storage. This is far less time than it takes to gather moisture that could cause phase separation of ethanol.