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Need to drain tank....how?

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Old 06-11-2007, 09:03 PM
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Default Need to drain tank....how?

hey guys,

I wanted to siphon the gas out of my tank so I can put some fresh gas in (been in winter storage)

I get the tube down only so far and I hit something, a baffle or something

anybody have any tips on how I can get this old gas out?
Old 06-11-2007, 09:23 PM
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There is a flap that stops gas from coming out of the filler neck in the event of a rollover or something like that. I heard with a stiff enough siphon tube you can push through it but the tube I used was small also. I drained my tank after I dropped it for pump install.
You may be able to create a siphon from the fuel line that connects to the filter but I'm not sure how easy that'll be.

The 3rd gen days were easy when there was just an overflow vent. We just pressurized the tank with air and it pumped the gas right out of the fuel line. Doesn't work on 4th gens (at least ls1) I'm guessing because that rollover flap.
Old 06-11-2007, 09:24 PM
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disconnect line at the fuel filter, get it to sit inside a gas can, then find a way to turn on the fuel pump (find the relay under the hood and jump it) carefully of course, it's gonna spray out hard!
Old 06-12-2007, 09:13 AM
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could I just unscrew my fuel selenoid and "aim" that into a bucket, since its attached right to the fuel rails

I know when I key on, the pump primes...but I'm sure if I started the car with that line open, I'd run lean in a second?
Old 06-12-2007, 09:17 AM
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You car wouldn't start up. Start by disconnecting the negative terminal. Remove the line going to the fuel rail, fit a larger hose over the fitting and clamp it securely. Place that into a gas can. Reconnect the negative terminal and jump out the fuel pump relay. Keep your eye on the can and watch for leaks.

Do you know how much fuel is in the tank?
Old 06-12-2007, 09:25 AM
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I have a full tank, thats the problem. I want to drain about 3/4 of a tank.

suggest anything else?
Old 06-12-2007, 09:29 AM
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Well, you can't siphon it. The only way is to have the pump push it out or try to drop the full tank and remove the fuel tank sending unit to siphon it.

You could go under the car and disconnect it from the fuel filter, put a hose on it. Energize the pump and drain the tank.
Old 06-12-2007, 09:46 AM
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I'll give that a try this afternoon

thanks!




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