SOLVED: Need to drop the fuel tank but it is currently 80% full

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JayHow

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I have been dealing with EVAP issues, exhaust leaks due to broken bolts at the manifold, and other issues I'm trying to address on my 2005 GMC Yukon SLT (4x4, VIN T, Non-Flex) to get it to pass emissions.

I replaced the charcoal canister and vent valve and can now fill my tank just fine. However, I noticed a leak at the fuel tank while replacing the canister and vent valve. The tank looks wet on the rear passenger side down to the bottom of the tank and I have noticed the smell a few times walking around the vehicle. It seems pretty minimal, I haven't seen any gas dripping on the ground at all.

I need to drop my tank and see what is causing it, but of course I just recently filled up the tank (at about 80% full right now). I am not sure how to go about safely handling this... Any suggestions? I live in an apartment and I don't have anything/anywhere to store the gas in if I were to pump or drain it from the filler hose. Can I still drop the tank that full and it will just be heavier, or is that dangerous/stupid? Will a shop drain the tank for me? If so, will it cost me an arm and a leg?

I have 0 experience with this as you can probably tell.
 

Scottydoggs

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id run the tank down to E. gas is like 8 lbs a gallon. so easy 200 lbs in a full tank.

the lock ring for the fuel pump on top of the tank likes to rust away, then leak from the top of the fuel pump.
 

justirv

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I have been dealing with EVAP issues, exhaust leaks due to broken bolts at the manifold, and other issues I'm trying to address on my 2005 GMC Yukon SLT (4x4, VIN T, Non-Flex) to get it to pass emissions.

I replaced the charcoal canister and vent valve and can now fill my tank just fine. However, I noticed a leak at the fuel tank while replacing the canister and vent valve. The tank looks wet on the rear passenger side down to the bottom of the tank and I have noticed the smell a few times walking around the vehicle. It seems pretty minimal, I haven't seen any gas dripping on the ground at all.

I need to drop my tank and see what is causing it, but of course I just recently filled up the tank (at about 80% full right now). I am not sure how to go about safely handling this... Any suggestions? I live in an apartment and I don't have anything/anywhere to store the gas in if I were to pump or drain it from the filler hose. Can I still drop the tank that full and it will just be heavier, or is that dangerous/stupid? Will a shop drain the tank for me? If so, will it cost me an arm and a leg?

I have 0 experience with this as you can probably tell.
I'll agree with @Scottydoggs on this one. Tank is very heavy when over a 1/4 tank, unwieldy, and since you're under it, you'll probably spill all over you. I was in a similar situation when I lost my fuel pump. I got a mechanical (hand pump) fluid transfer pump and filled a couple 5 gal fuel jugs.
 

TollKeeper

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You can use a tool to separate the supply line at the fuel rail, and then put a hose on that, and run it to another car or gas can, and drain the tank. Once thats all setup, you run a hot wire to the fuse for the fuel pump, and pump away!

I did this recently on a truck I sent to auction.
 

strutaeng

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If this was a fuel pump job and truck was dead with a full tank of gas, you'd be SOL.

But for EVAP that doesn't affect driveability, just keep driving until tank is nearly empty.
 

viven44

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If this was a fuel pump job and truck was dead with a full tank of gas
That's just my game, lol... (coming from the kludgy world of dual fuel tanks + selector valve).. What I usually do is hook up my spare transfer pump to the sending unit and siphon out all the fuel.... I have an Edelbrock 17301 spare (which I run on my carbureted trucks.)

I imagine the fuel sending unit is not very accessible on these trucks... so I'd probably try to hook this transfer pump to the inlet line of the fuel filter and try to siphon out as much fuel as possible.... of course, the fuel needs to be stored or fill another vehicle. I have 25ft rolls of various diameter fuel lines in my garage always so that helps....

A pump like the one below might work for temporary situations like this

 

MrMonte

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I replaced the fuel 2x on my 1999 Suburban and each time I had close to 40gal of fuel in the tank. I used some plywood and a floor Jax made for easy fuel pump sway, took about 1hr each time.
 

viven44

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Another idea to drop the fuel tank is to use a transmission jack or 2... Anytime I see a Harbor Freight jack on Facebook used "1 time only" for $50, I buy that sucker! It is a lifesaver. On a large tank like this, you can definitely use 2 jacks
 

Fless

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You can use a tool to separate the supply line at the fuel rail, and then put a hose on that, and run it to another car or gas can, and drain the tank. Once thats all setup, you run a hot wire to the fuse for the fuel pump, and pump away!

I did this recently on a truck I sent to auction.

^^ This^^ Let the onboard fuel pump do the work and donate the gas to a friend or neighbor. Or run it for the miles it takes to get it low.
 

rockola1971

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You can use a tool to separate the supply line at the fuel rail, and then put a hose on that, and run it to another car or gas can, and drain the tank. Once thats all setup, you run a hot wire to the fuse for the fuel pump, and pump away!

I did this recently on a truck I sent to auction.
You know at any OBD2 connector you can jump 2 terminals with a paperclip to turn on the fuel pump, right? Or you can use a bidirectional scanner if you have one to command the fuel pump on too or goto fuel pump relay and pull it and jump the 2 terminals at the socket that attach to the relays normally open contacts which are #30 & #87.
GM fuel pump pin is Pin#9, jump it to ground with key on and pump is running continously.
 

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