Text from a Hemmings article.
"Ethanol gas is hygroscopic, which means it absorbs water more easily than gasoline. That leads to water condensation inside fuel tanks. Ethanol also erodes fiberglass tanks, rubber hoses and plastic fuel lines. It contributes to rust in fuel systems by creating condensation in the unfilled portion of gas tanks".
So if I understand correctly the system would be a sealed gas cap, a rollover vent, a charcoal canister and a vacuum port on the carburetor. Would this system also remove water vapor in the tank (as long as the engine is running) or make it worse?
I dread the day when the government outlaws non-ethanol gas.
Every modern car made in the last 20+ years uses this system so I thing you will be fine on water vapor. The more important thing on your rebuild especially if you have a old stock truck is those hoses. Modern gas eats them alive with ethanol They should be replaced with modern stuff.
