I really wonder if/how much air is entrained in a such a low viscosity liquid such as gasoline? I am sure it is entrained, but seems any air would would be rapidly released due to gravity, etc, and unless fuel pickup was adjacent to the fuel return, problem would be very minor, if at all. I'm sure there is a video somewhere demonstrating the issue, one way or the other.
I use to make clear plastic tanks just to see whats
happening inside to make sure we were ok... there is
a fair amount of foaming going on in there.. most dont
think fuel foams up but it does with the air thats in
there... and we would measure the pressure inside the
tank.. most of the time it was in inches of water.. but
I did see over 70" of water in there(greater than 2 psi)..
the RVP(Reed Vapor Pressure) of the fuel makes a big
difference.. higher the RVP the more pressure it builds
in the tank
