Gasoline

[CREWZIN]

Before I throw in something I read today in a magazine, let me ask a question:

If I pour an ounce of gasoline on the pavement outside, then take an ounce of gasoline and put it into a glass jar with a half tightened lid on it, how much gas will be left, after evaporation comes into play, in about 10 minutes?

We should all know that the gas on the pavement would be gone. Gas in the jar, lower but still a lot left.

As I said, that's the evaporation process.

Most people don't know that most gas stations have a collapsible fuel bladders inside the underground tank. The reasoning behind this is: as the fuel is dispensed thru the pumps the collapsible bladder collapses from the top and there's less air inside the underground tank. The less air (like the glass jar in my question above) the less evaporation of the gas in the tank.

We can't do this in our vehicle gas tanks of course, but, if we only use half a tank of gas at a time before filling up, then there's less air in the tank and less evaporation taking place.

As I said, this was a magazine with this theory and their estimate was something like loosing up to a gallon of gas before you could empty the tank running around town.

Now of course if your on a trip of hundreds of miles and your going to use a tankful every couple of hours, this theory doesn't hold true, but if it takes you a week to go thru a tankful, then there's a lot of evaporation taking place.

Makes sense to me. Any thoughts??

P.S. As an afterthought, it also hurts less on the wallet filling up only half a tank.

[ucantcme]

Since gas prices reached into the $3.00 mark, I've only been filling it up halfway ($25 from E to half!).

Thanks for sharing!

[Hooligan]

I have never left my tank go below 1/4, if I find gas at a lower price, I fill up even IF it is only 1/2 tank left.

[bobs turbo pt]

prices have hit the 4.00 and above mark here in new york !!

[soonercruiser]

1. Keeping the tank fuller lessens evaporation! (Remember the thing called "vapor pressure" from highschool physics class?)
2. Letting your tank go down to E to 1//4 is asking for early replacement of the fuel pump and sensor (both of which are located inside the tank itself). No fuel = no cooling or lube of the pump = replace fuel pump more often. And, it is a real "pain", I've heard! (see some previous posts on the subject)

[ucantcme]

Originally Posted by soonercruiser

1. Keeping the tank fuller lessens evaporation! (Remember the thing called "vapor pressure" from highschool physics class?)
2. Letting your tank go down to E to 1//4 is asking for early replacement of the fuel pump and sensor (both of which are located inside the tank itself). No fuel = no cooling or lube of the pump = replace fuel pump more often. And, it is a real "pain", I've heard! (see some previous posts on the subject)

I always ride my tank when the needle is resting on the "E" position - Been driving the PT for almost 3yrs, and over 50k miles and never had to do anything like that (yet)

[soonercruiser]

Exactly...."Yet"!
See some of the previous posts by some P{Ters, who are actually mechanics.