[GSTRYDR]

Originally Posted by G-Oil Guy

Ok, let me see if I can clarify a little:

Claim: Temperature affects level of vaporization of fuel
My response: This is true.

Claim: The temperature fluctuation in the underground storage tanks can affect the amount of fuel you get so you should only get gas in the morning
My response: these tanks are surrounded by concrete most often when they're installed and they're installed at such a depth that I doubt there is much measurable temperature fluctuation in the tank. Thus the impact on fuel vaporization is probably negligible.

Claim: vapor recovery systems are robbing you of fuel and not providing an exact amount of gasoline
My response: Gasoline pumps are required to be certified on a specified interval (that varies state to state) by the Department of Weights and Measures to prevent fraud and would most likely be caught.

Claim: Pumps induce vaporization of fuel by due to the speed at which they pump and they are not temperature compensated to reduce that.
My response: in refineries and terminals to move that large of a volume you use centrifugal pumps which can induce some vaporization which can make the pump "knock" (there is a real term for it and its escaping me at the moment) causing the liquid amount to be off. HOWEVER, with the small volumes that the individual pumps dispese, I think they might use positive displacement pumps which pump a fixed volume that cannot change. But I'm not positive if they are PD pumps.

Hope that helps.


Also, the stations themselves are most often owned by independent owners who pay a licensing fee to use a big companies name. If you get screwed over, it's by them. The guys who pay the big companies on gasoline are the terminals like the guy was claiming he works at. By the time the gasoline gets to your car, the Big Guys have been paid already.

The term is Cavitate. Just helping out.