How can I drain my fuel tank?

Old 04-23-24, 04:18 PM
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How can I drain my fuel tank?

1995 GMC Sierra 1500 4x4. It has sat for 6 years. Gas in tank is obviously no good. I can put fuel in carb and get it to fire but it doesn't last. Is there a possibility of that I can disconnect the fuel line at carb and have the fuel pump empty the gas tank into a container? Or, is there a better and easier way to empty the gas tank?
Old 04-23-24, 04:51 PM
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It would take days to drain that much fuel with the on-board fuel pump.

Specs show that as a 34 gallon tank.
How much fuel is in there ?
Six years is not that old. You may be able to add new to mix with old.
An additive like Seafoam too.

Your current problem is more likely a delivery problem or gummed up injection system.
Not sure what that uses for injection. Could be injection into the throttle body.
It's based on the engine.
There should be a way of checking incoming fuel pressure.
That should be checked to see if the pump is pumping.
sofasurfer voted this post useful.
Old 04-23-24, 05:48 PM
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Short bed, 26 gallons. Shouldn't be 10 gallons in it. I'll see if I can figure out if its pumping gas.
Old 04-23-24, 05:54 PM
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If it sat for 6 years, I'd drop the tank & pump the fuel out with a pump of your choice, or just dump it in a foot tub or some big mouth container as such.
I'd replace that fuel pump regardless. Not that it may not pump fuel today but if it's sat for 6 years, I'd be afraid of seals, o-rings, diaphragms, just gunk or already a bad pump etc. Which means you're gonna have to drop the tank & pull the pump later.
I'm not saying it is bad, but I'd bet it is more likely to go bad than not.
While I have the tank dropped & the pump out, I'd get recommendations of cleaning the inside of the tank. I'm also betting there's going to be at minimum sediment & small debris in that tank from condensation which may have also caused some rust. If you don't clean/rinse it out & slosh it around & try to remove some of that trash in there, it's also going to give you trouble, at least I'd bet more likely than not. At minimum some condensation/water in that fuel.
Should be 2 straps on the tank, a fuel line & a return line & the rubber filler hose with a radiator type clamp.

If by chance you decide not to drop the tank, you could remove about 6 or so bolts from the bed & move it around to get to the pump, &/or siphon that old gas out. Depending on the tank & the bed, I have seen people raise only one side of the bed to access the tank/pump etc.

That's just my approach.
Old 04-23-24, 09:35 PM
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would probably take the fuel filter off under the drivers side frame rail cycle the key see if you get any fuel flow with the line off if you do you can remove the oring so you dont lose it attach a hose run it to a gas can and then hook up power to the in the tank pump wont be terribly fast but would expect 15-20 gph reinstall the oring and a new filter when your done.
but there is a decent chance the pump may not be working any longer which would mean installing a new pump anyway.
Old 04-24-24, 06:16 PM
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I had a similar situation last year with a Thunderbird I don't get to drive as much as I would like. Couldn't get any fuel to the injectors for it's weekly fire up. I drained the tank at the fuel filter but fresh fuel still wouldnt make it to the injectors. Pulled the tank and found a rotted short piece of fuel line that was gumming itself up with rotted line debris, Replaced the line and the fuel pump. Works ok now.

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