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Draining C7 Fuel Tank?

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Old Nov 3, 2016 | 12:31 PM
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Default Draining C7 Fuel Tank?

How do we drain the C7's fuel tank? I'm currently full of 93 and need to drain it to fill with E85 in order to make my Eth. content go up,
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Old Nov 3, 2016 | 03:38 PM
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Drive it.
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Old Nov 3, 2016 | 03:50 PM
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Originally Posted by DP RS
Drive it.
That would work
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Old Nov 3, 2016 | 04:01 PM
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You could remove the inlet nozzle and siphon the left tank, but you will not get the fuel in the right tank since only a jet siphon pump transfers fuel to the left tank as fuel is used.
The fuel system is designed to empty the right tank first since the engine is supplied fuel from the left side only.


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Old Nov 3, 2016 | 04:14 PM
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I needed to drain some gasoline in my previous car, and it had a screen in the fill line preventing siphoning.

So I pulled the fuel line off the motor and put it in a bucket. Then, pulled the fuel pump relay, and switched it on manually. Turned it off a few times to empty the bucket, but it was successful.
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Old Nov 3, 2016 | 11:48 PM
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I just drilled a 1.75" hole in my tank and that drained it pretty quickly


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Old Nov 4, 2016 | 03:36 PM
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Originally Posted by 555ctsv
I just drilled a 1.75" hole in my tank and that drained it pretty quickly


And then just cork it closed!!
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Old Nov 4, 2016 | 04:39 PM
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Originally Posted by Dizzyscure1
How do we drain the C7's fuel tank? I'm currently full of 93 and need to drain it to fill with E85 in order to make my Eth. content go up,
Unless you have the proper tools to disconnect the fuel line at the motor and a switchable relay to put in place of your fuel pump relay, I would just drive it "nicely" until the level drops to the amount you are looking for.
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Old Nov 4, 2016 | 05:04 PM
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Originally Posted by Lance@MTI
Unless you have the proper tools to disconnect the fuel line at the motor and a switchable relay to put in place of your fuel pump relay, I would just drive it "nicely" until the level drops to the amount you are looking for.
thanks for all the input guys, I ended up driving the car until the fuel was low enough. For sure miss a return style fuel system in this C7 :/
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Old Jun 24, 2018 | 03:28 AM
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Originally Posted by joemosfet
I needed to drain some gasoline in my previous car, and it had a screen in the fill line preventing siphoning.

So I pulled the fuel line off the motor and put it in a bucket. Then, pulled the fuel pump relay, and switched it on manually. Turned it off a few times to empty the bucket, but it was successful.
Hi, did you manage to drain both sides of the tank?
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