Gas Fill Tip

Pumping gas.... more bang for your buck!

Mr. X has been in petroleum pipeline business for about 31 years, currently

working for the Kinder-Morgan Pipeline in San Jose, CA. They deliver

about 4 million gallons in a 24-hour period from the pipe line; one day

it's diesel, the next day it's jet fuel and gasoline. They have 34

storage tanks with a total capacity of 16,800,000 gallons. Here

are some tricks to help you get your money's worth:

Morning is Better

Fill up your car or truck in the morning when the temperature is

still cool. Remember that all service stations have their storage

tanks buried below ground; and the colder the ground, the denser the

gasoline. When it gets warmer gasoline expands, so if you're filling up

in the afternoon or in the evening, what should be a gallon is not

exactly a gallon. In the petroleum business, the specific gravity and

temperature of the fuel (gasoline, diesel, jet fuel, ethanol and other

petroleum products) are significant. Every truckload that is loaded is

temperature-compensated so that the indicated gallonage is actually the

amount pumped. A one-degree rise in temperature is a big deal for

businesses, but service stations don't have temperature compensation at

their pumps.

Don't Load when they Unload

If a tanker truck is filling the station's tank at the time you want

to buy gas, do not fill up; most likely dirt and sludge in the tank is

being stirred up when gas is being delivered, and you might be

transferring that dirt from the bottom of their tank into your car's

tank.

Half Full is better

Fill up when your gas tank is half-full (or half-empty), because the

more gas you have in your tank the less air there is and gasoline

evaporates rapidly, especially when it's warm. (Gasoline storage tanks

have an internal floating 'roof' membrane to act as a barrier between

the gas and the atmosphere, thereby minimizing evaporation.)

Take your time

If you look at the trigger you'll see that it has three delivery

settings: slow, medium and high. When you're filling up do not squeeze

the trigger of the nozzle to the high setting. You should be pumping at

the slow setting, thereby minimizing vapors created while you are

pumping. Hoses at the pump are corrugated; the corrugations act as a

return path for vapor recovery from gas that already has been metered.

If you are pumping at the high setting, the agitated gasoline contains

more vapor, which is being sucked back into the underground tank, so

you're getting less gas for your money. Hope this will help ease your

'pain at the pump'