Overflowing fuel filler?

H. L. Chauvin said:
Hi Wayne,

Never thought of this before, i.e., that gasoline stored below ground further north could be at a lower temperature than gasoline stored underground further south.

Years ago, after hearing about the differences of "water" cooling residential A/C compressor coils as opposed to "air" cooling same with the additional cost of operating an electric fan motor, I remember measuring the water temperatures of water in the month of July, immediately drawn from two water wells, where one was further north, one was further south and they were about 200 miles apart.

In 200 miles, there was about a 20 degree rise in the well water further south.

Appears what this information may mean, depending on various locations, (even in mountainous regions with melting ice), is that this fuel overflowing possibly caused by expansion is more likely to occur where the ground temperature is cooler.
Click to expand...

6ft summertime ground temps in northern MN are around 43* given an ambient air temp of 80* and a hot engine and radiator blowing 160* temps on a gas tank along with a hot sun beating on the tank, its no wonder the tank is making gas. I'm sure some engineer here can figure out the increase in volume of gas given the coefficient of volumetric expansion for gasoline. To hard for my tired old noodle.:confused:
 
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Airliners are typically fueled from hydrants in the ground using a fueling apparatus to transfer the fuel. So the fuel is generally cool.

At some stations, the fueling was done with trucks.

Occasionally, if the MD-80 was fueled with warmer fuel from a truck, you would reach tank capacity in gallons before reaching the required fuel load in pounds, as the fuel was less dense.

This happened to me only once in 22 years of flying...

Fuel load required for dispatch was always measured by weight, as fuel burn was calculated in pounds per hour.
 
This exact thing happened to me just last week. Filled up (non-ethanol) from my above ground tank. Air temp was low to mid 40's. Tucked the "A" into its temp controlled bay that was around 62. An hour later I smell the gas and see it coming out the fill and begin cleaning up and air out the bay- I hate that smell! I assumed it was the temperature change and made a mental note to fill it not quite so full.
 
Once on a Model A car rally we came upon another members car parked on a steeply cambered road and gushing petrol out of the filler cap and down the kerbing. As we watched, the sun went behind a cloud and the leaking stopped. Then the hot summer sun came out from the cloud and within seconds the flow started again.
Because he was parked outside a horse racing betting shop, we were vigilant for smokers discarding their ciggies before entering the shop to place bets, and stood there for half an hour, warning people not to throw live butts into the kerb. I argued with one woman and stamped on the live butt she threw down before it ignited the fuel.
But this half hour enabled us to see repeated cycles of expanding petrol leak down the road. The speed of reaction and expansion from the sun as it went behind clouds a then re-emerged amazed me. At least half a gallon of gas left the tank, due to the extreme angle the car was on due the the road camber.
SAJ in NZ
 
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I think expansion is something we used to allow for but have forgotten about with modern cars and modern fuel dispensing equipment.

We were always careful to leave room with the tractors and farm equipment when using above ground fuel tanks and manual shutoffs...
 

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I fill to the top of the glass most of the time, and with no-choice California crap gas. I use a PVC extension piece, and have never had any gas overflow, unless I made a very sharp, abrupt turn while the tank was completely full.
 
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