LT1-LT4 Modifications 1993-97 Gen II Small Block V8

Need To Siphon Out Old Gas

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Old Jul 26, 2016 | 08:29 AM
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Default Need To Siphon Out Old Gas

This is what im using
http://www.partsreloaded.com/PWC/Acc...oY0aAuWk8P8HAQ

No luck what so ever. Now im doing the Trap Door method next week for changing the fuel pump and my question is would I be able to siphon out the gas through the hole that way or is there another way of doing it? The gas is about 1 year old and has become stale.
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Old Jul 26, 2016 | 08:45 AM
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I tried to use that method through the fill tube but it did not work. I also syphoned my tank from the top when I did my fuel pump and that worked fine as I was able to get all the gas out and see into the tank (trap door method as well).

You can also run a fuel hose to the Schrader valve on the fuel rail and put the other end into a gas can. Then you can use the hotwire plug under the hood to manually turn the pump on by connecting a wire to the fuel pump relay plug on the passenger side by the pcm ---this will turn on the fuel pump relay and allow the fuel pump to run while the car is off. You can just run a direct wire to the plug from the 12 volt red box/battery or put a momentary switch in between to turn it on and off easier.
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Old Jul 26, 2016 | 09:25 AM
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I do as Nostang said and undo a fuel line then jump the relay and just let it pump out
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Old Jul 26, 2016 | 09:53 AM
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From: Jackstandican
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I believe there is an anti-siphoning device in the fill neck. You can either manually engage the pump, or when replacing your fuel pump you will have access to the inside of the tank. If you chose to use the pump make sure to pay attention and shut it off once there is no more continuous flow. Don't want to burn it up.
How much gas in the tank and how old is it?
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Old Jul 26, 2016 | 10:10 AM
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The shaker hose will work just fine through the trap door also
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Old Jul 26, 2016 | 12:21 PM
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You need a gas siphon that is compatible with newer vehicles if you want to siphon it out from the tank. Easiest way is to siphon gas through the trap door.
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Old Jul 26, 2016 | 02:51 PM
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Disconnect fuel line at fuel filter, put line in a can, use fuel prime hotwire and connect to 12v, sit back n enjoy
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Old Jul 26, 2016 | 10:00 PM
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^^You can do that or just drop the tank like I did when I swapped in a larger fuel pump. It was pretty easy since the rear end was out of the car. GL
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Originally Posted by SS RRR
I believe there is an anti-siphoning device in the fill neck. You can either manually engage the pump, or when replacing your fuel pump you will have access to the inside of the tank. If you chose to use the pump make sure to pay attention and shut it off once there is no more continuous flow. Don't want to burn it up.
How much gas in the tank and how old is it?
Resurrecting an old thread through a search.

I have 3/4 of a tank of 4+ year old gas. I also have a Walbro pump with the sock along with a 5 year old fuel tank. I don't recall any anti siphoning device. But if there is one and I have to use the fuel pump to get the gas out will the crap gas clog up the sock?
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Old Nov 1, 2019 | 02:35 PM
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From: Jackstandican
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I have no idea what condition the gas could be in. I do remember seeing threads where people were saying they couldn't siphon through the filler neck. You have a trap door for the fuel pump? You can buy a battery powered siphon and take it out that way. Or simply run it and change out the sock and fuel filter. :shrug:
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Old Nov 11, 2019 | 04:20 AM
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Originally Posted by SS RRR
I have no idea what condition the gas could be in. I do remember seeing threads where people were saying they couldn't siphon through the filler neck. You have a trap door for the fuel pump? You can buy a battery powered siphon and take it out that way. Or simply run it and change out the sock and fuel filter. :shrug:
I regret not doing the trap door.
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