how on earth i depressurize the fuel system?

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johnshop
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Joined: Thu Aug 16, 2012 8:36 pm
Car: 1995 nissan 300zx na 2+2
Location: galveston, tx

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i have a giant gas leak and a cracked hose and i need to depressurize the system right? if so, how do i do it?

i've tried to look and they talk about opening my gas tank and something about a relay? i don't get it, i even read that i should just go slow and let the pressure out of the hose? WUT?

hopefully someone can answer me fast, i only got like 1 hour more of light ahahah :gapteeth:


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Ziggy1621
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If you read about the relay, then you're on the right track, head back to that howto and follow it :) that's the correct way

johnshop
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they didn't explain it, how about disconecting the fuel pump under the spare tire? and running the car until it dies? would that work?

i pulled my fuel pump connector off and i cranked the car untill it stalled, then i cranked it like 3 times to relieve pressure, i think that's it uh?

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t.mcginley.jr
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Take the fuel pump fuse out, its behind the kick panel on the drivers side where your left foot rests. There should be some plastic retainers holding it on, after removing it you should see the fuses. Once you remove the fuse, crank the car until it dies (which is when the fuel lines are empty. You could also remove the gas cap for good measure. When you remove the fuel line after that some gas might shoot out but not nearly as much as if it was full. What's leaking anyway?

johnshop
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the fuel damper lower line :Image so it seems i will have to take the balance tube out.... great. not hard tho.

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Ziggy1621
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Be gentle with the balance tube orings

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t.mcginley.jr
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Nah not hard. I'm actually in the process of putting my balance tube and fuel damper/pressure regulator back on after my rebuild. Getting that hard plastic part with the holes in it over the new hose was a royal PITA. But yeah all new fuel hoses is the way to go.

johnshop
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t.mcginley.jr wrote:Nah not hard. I'm actually in the process of putting my balance tube and fuel damper/pressure regulator back on after my rebuild. Getting that hard plastic part with the holes in it over the new hose was a royal PITA. But yeah all new fuel hoses is the way to go.
it got too late i have 0 light so i will have to continue tomorrow morning, wow almost 2 hours to remove a little 3 inch piece of fuel hose... and i didn't even finish, tomorrow is a new day :gapteeth:

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t.mcginley.jr
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johnshop wrote:
t.mcginley.jr wrote:Nah not hard. I'm actually in the process of putting my balance tube and fuel damper/pressure regulator back on after my rebuild. Getting that hard plastic part with the holes in it over the new hose was a royal PITA. But yeah all new fuel hoses is the way to go.
it got too late i have 0 light so i will have to continue tomorrow morning, wow almost 2 hours to remove a little 3 inch piece of fuel hose... and i didn't even finish, tomorrow is a new day :gapteeth:
Been there, done that lol after a while you can't even tell what you're looking at. good luck

johnshop
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My god getting the hoses are a b**** to get on the tubes....

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Ziggy1621
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Don't just grab and pull ;) use a pair of pliers and gently grab the hose right where it slides onto the hard pipes. Twist back and forth until they break loose, then you should be able to twist and slide them off by hand.

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t.mcginley.jr
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Also, once you break the hose loose how Ziggy said, you can use a thin screwdriver to pry part of it up and squirt just a bit of WD-40 in. It will lube up between the hose and metal and make it slide off much easier.

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t.mcginley.jr
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Oh and when your reinstalling the any of the hoses, not just fuel, use vaseline on the metal parts and the hose will slip right on.

johnshop
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You guys are really helpful :).

About the Vaseline, could I use something else? Like a little bit of liquid soap maybe? I have no Vaseline and my closest anything is like 3 miles walking. Ahaha

nissanfreak12
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johnshop wrote:You guys are really helpful :).

About the Vaseline, could I use something else? Like a little bit of liquid soap maybe? I have no Vaseline and my closest anything is like 3 miles walking. Ahaha
All you really need to do is get them wet. A tiny bit of water, very minimal engine oil, and I mean a very thin layer will work just fine.

johnshop
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my neighbor had vasseline! sweet, the car is running again leak free, im so glad.

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Ziggy1621
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Nice job dude!


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