Gas Evaporation?

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andrew-75c10

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Is it possible that the gas from my tank is evaporating off (I assume it's not getting siphoned because I keep it behind a locked gate but maybe I could put a camera up). The gas cap is pretty old and rusty, and the fuel filler pipe is a little bent out of shape. I put a new rubber seal, but I'm not sure if the gas cap is doing its job.

Last week I parked my truck with a few gallons of gas left in the tank, and today it wouldn't start until I added another gallon from a jerry can I had on hand. The camera on my phone is busted, but I'll try to get some pictures up.
 

Ricko1966

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Absolutely fuel can evaporate from fuel tanks.Thats why manufacturers started putting in evaporative emission systems, to keep countless gallons of evaporated fuel out of the atmosphere.The side benefit is you get less condensation(WATER) in the tank and get to burn more of the fuel you buy. you could also have a small fuel leak in the tank( pretty common) or both.
 

80BrownK10

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Is it possible that the gas from my tank is evaporating off (I assume it's not getting siphoned because I keep it behind a locked gate but maybe I could put a camera up). The gas cap is pretty old and rusty, and the fuel filler pipe is a little bent out of shape. I put a new rubber seal, but I'm not sure if the gas cap is doing its job.

Last week I parked my truck with a few gallons of gas left in the tank, and today it wouldn't start until I added another gallon from a jerry can I had on hand. The camera on my phone is busted, but I'll try to get some pictures up.
Not this time of year unless you live in the southern hemisphere. It would take awhile for several gallons of gas to evaporate in a tank that's even open.
 

80BrownK10

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Not this time of year unless you live in the southern hemisphere. It would take awhile for several gallons of gas to evaporate in a tank that's got even a faulty cap on it.
 

Salty Crusty

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Check your gauge and/or sender
 

75gmck25

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My guess would be a cracked rubber fuel line that is letting gas leak out, and is also preventing the fuel pump from drawing fuel well when the tank is low. Ethanol in the gas messes up the old rubber lines, and there are several connected to the sending unit that are hard to see.

Fill the tank at least half full, and then leave it running when parked over a clean patch of cement driveway. Look for leaking fuel while running and after shutdown.

Bruce
 

82sbshortbed

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Idt a couple of gallons would evaporate in a week. But, could be wrong tho. I think it'd have to be really hot outside and cap off or something.
 

seniorbear69

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i thort he said rusty cap .maybe i read wrong ! but sad to say it stoped disapearing fule .sum scum bag helping them selves coz thay to good togo pay for thear fule same as the rest of us
 

Turbo Dog

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There may not be a problem at all. You can drive in with only a couple of gallons in the tank and then not start if that isn't where the fuel pickup tube can get to it. The couple of gallons keeps moving around while you are driving allowing you to get closer to empty.

That happened to a friend lately with a different vehicle. He pulled in and parked it then couldn't get it to restart. I took a look for him and found he wasn't getting fuel. I told him he was out of fuel and he said "no way, I drove in here even though it was almost out of fuel. I was gonna fill it when I leave." Keep in mind he is an engineer and asked me not to tell anyone.
 

SirRobyn0

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I think you have a tiny leak. If you have a plastic skid shield on your fuel tank and develop a teeny tiny leak, it can get out of the tank and then evaporate off before you see it.
 

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