Editing Forums/Z31P/z31-repairs-forums engine-mechanical/dropping the gas tank…need help

{{ForumImport
|op_user=zlover23
|op_date=2011-04-22 00:04:38
|post_count=13
|archive_url=/Z31performance_archive/forum/z31-repairs-forums/engine-mechanical/14172-dropping-the-gas-tank-need-help.html
}}

'''zlover23:''' <small>(2011-04-22 00:04:38)</small>

my z31 has some old, bad gas that i need to get out of the tank. ive never dropped a gas tank before and was wondering how difficult it is to do. before starting, i want to make sure i can do it and i have everything to do it. so what do i need to disconnect before actually removing the tank? do i need any special tools? any helpful tips would be greatly appreciated!

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'''Z_Karma:''' <small>(2011-04-22 00:14:48)</small>

If you are just draining the tank, there is no need to drop it.

There is access to it through the hatch area floorboard, beneath the foam.

Before you proceed, it would be advisable to download the FSM and read it or get a haynes manual.

FSM's can be found on Xenon's site:

[http://www.xenonz31.com/reference.html http://www.xenonz31.com/reference.html]

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'''zlover23:''' <small>(2011-04-22 00:57:17)</small>

are you talking about where the fuel pump is located? just take the fuel pump out and syphen the bad gas out through that hole?

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'''Z_Karma:''' <small>(2011-04-22 01:11:14)</small>

Why use a siphon when you have a pump right there already?

'''Step 1

Disconnect the fuel line from your fuel rail, you want the one coming off of the filter.

'''Step 2

Extend that fuel line off of the filter with a barbed fitting and a long section of hose

(it doesn't have to be fuel injection hose, just plain fuel line will work) Put the other

end into a gas can or other suitable container.

Step 3'''

Turn the key to the on position. This will power the fuel pump and it will eventually empty

the fuel tank into the gas can. Turn it off when it starts to sputter, meaning the tank is about empty.

Step 4'''

Either pull the pump and inspect the tank for any debris or crap OR reconnect the fuel line to the fuel

rail and fill the tank with fresh gas.

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'''Nathan18:''' <small>(2011-04-22 01:11:28)</small>

I will give some advice on this as well..

When I bought my Z, it had been sitting for close to 7 years, with half a tank of gas still in it. A friend and I dropped the tank, but, I didn't think about flushing the fuel lines (rather stupid I know). So I was still running that bad gas that was sitting in the fuel lines, through the engine.

So, what I'd suggest is, after emptying the gas tank, put approx. gallons of gas in it, then remove the fuel line right before it hit the "track" to the fuel injectors, then crank it and let it flush all that bad fuel out. Then put some good injector cleaner in and you should be good to go!

EDIT: we posted at the same time. :nanan?re

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'''zlover23:''' <small>(2011-04-22 01:20:26)</small>

that is exactly what i needed to know! thanks for all the help!! :-D

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'''nismopu:''' <small>(2011-04-22 01:43:54)</small>

My car had been sitting for over 6 years(87t) and I just got in it and drove it........started right up. It took about a day to burn through the bad/old gas of just drivin around town running errands.

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'''michaelp:''' <small>(2011-04-23 03:57:31)</small>

{{Quote|user=|}}

The problem with that is the fuel pump will only run for 5 seconds unless you start the engine, which you aren't going to do with the fuel line unhooked. Just sayin'.

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'''NissanEgg:''' <small>(2011-04-23 04:04:49)</small>

Pull up carpet and foam.

Remove the big circle plate in floor.

Then remove fuel level sending unit.

Then insert a hose and syphon out the old gas.

Then reinstall everything and add new gas.

Remove fuel filter and attach hose to fuel line and insert other end into a clear bottle.

Have friend crank engine and watch the fuel come out into the bottle. Keep doing this until clear clean fuel comes out.

Install new fuel filter and reconnect line to fuel rail.

Then start engine and let idle till warm and then drive.

Done.

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'''zlover23:''' <small>(2011-04-25 01:26:20)</small>

well thanks for all the help. i just decided to drop the gas tank that way i could get every drop of gas out of it. it was a pain in the a** but man it made a HUGE difference! throttle response has greatly improved, idles much smoother, and just feels well…faster.

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'''JSM:''' <small>(2017-11-08 00:33:07)</small>

So I'm assuming from reading this that we don't have drain plugs like the Z32 do! Rats!

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'''Dunkine:''' <small>(2017-11-12 00:04:02)</small>

{{Quote|user=JSM|So I'm assuming from reading this that we don't have drain plugs like the Z32 do! Rats!}}

Only if you turn it upside down :P

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'''JSM:''' <small>(2017-11-12 00:38:06)</small>

Hehe!

I got it. I disconnected the line going into the rail, dumped it into a gas can, hardwired the pump and it took about 10 min. I only had about 3 gallons Of gas.