Water molecules attract themselves to other water molecules. That’s what causes “surface tension”. My understanding of the way ethanol works is that it interferes with this process, attracting water molecules to itself. This is not inconsistent with Tester’s earlier “phase separation” description nor with the BG description. My question with Tester’s description would have more to do with molecular weights, as the sinking to the bottom description leaves me a bit uncertain.
As regards filling the tank, vapors pass through the charcoal canister on their way out the tank, capturing the hydrocarbon molecules in the carbon on the way out. EPA regulations require that no HC molecules be allowed to escape during refueling.
Re: the “sealed systems”, I’ve always clarified that they’re sealed from the pump to the injector. And they are. The airspace in the tank is not sealed, but does breath through an activated charcoal bed.
However, I still think that while this would all make great technical discussions it’s a diversion from the OP’s problem. I still think the OP’s problem is other than icing. I confess to being the one who sidetracked the issue, and will try to avoid this bad behavior in the future. But I’d really like to try to get this thread back on track. The poor OP must be going crazy at this point.
In Minnesota, we’ve been struggling with E10 gasoline since 1993 since the state mandated it as the standard motor fuel.
Here’s the one thing you need to remember with ethanol in gasoline. Ethanol will mix with gasoline for a short period of time. This is why at refineries the have the pure gasoline is stored in one tank and the ethanol is stored in another tank. This is because if they store the gasoline with the 10% ethanol blend, the ethanol will phase seperate out of gasoline along with any moisture that the ethanol absorbs and settle at the bottom of the tank.
So instead, they keep the pure gasoline in one tank, and when they fill the tanker truck they fill it 10% short of a full load. Then pull up to the ethanol tank and finish filling up the tanker truck with ethanol. This allows the ethanol along with the moisture to mix with the gasoline thru agitation. Then when the truck delivers the E10 gasoline to the station, the despensing of the gasoline into the underground tank also agitates the ethanol/moisture where it stays suspended.
The problem with ethanol is, it’s not immiscible in gasoline. Or in other words, it’s resistant to mixing with gasoline. So if you have an alcohol that doesn’t mix well with gasoline, along with the moisture that alcohol absorbs, it doesn’t take much for the alcohol/moisture to phase seperate out of the gasoline.
Where with isopropyl alcohol, it is immiscible in gasoline or mixes well. And it also absorbs moisture. But it doesn’t phase seperate out of the gasoline along with the moisture.
In regard to phase separation, it’s the amount of water that matters, not the length of time. E10 can stay mixed for years with no problem as long as excess water doesn’t get into the mix.
In re to no cold weather start w/my Taurus, when the weather warmed up to about 35-40 degrees, I was able to start it, and drove it right to our friend/certified mechanic. He ended up being able to fix the problem (when it got cold enough again to duplicate it) by replacing the relay switch (for the fuel pump, I believe) - the pump itself tested good. Car has started every time since for at least a week, even yesterday when it was about -8 degrees here in Indiana. Today, not so lucky…lots of crank, but no start…back to the drawing board!