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What to do with old fuel line?


Sanchez

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I got my car up and running after being down for a few weeks with a bad case of old wire syndrome.  This smoothed out a whole lot of electrical issues and all of the systems seem a helluva lot more stable.  But in that time I started a new job, and I cannot drive this car at all without saturating all of my clothes with the sweet smell of gasoline (not to mention the girlfriend won't let me drive her anywhere in it cause she can't stand the fuel smell).

 

I have read all of the posts about fixing the fuel/exhaust smell in the cabin, plugging firewall holes, real hatch seals, getting mixture set right (still working on that one), etc... and I am going to tackle those soon.  I also found out that the lines from the fuel fill to the tank leak when slightly overfilled and I am correcting that now.

 

I also remembered a bit of advice given to me by a Z-Expert when he worked a bit on my car about a line running from the tank to original mechanical fuel pump.  He suggested a way to connect it to the intake manifold using a valve and some other fitting, but I forgot where to run the hose to and what direction the valve needs to face.

 

post-27768-0-41078200-1458173452_thumb.jpg

It is the hard line that my fingers are on.

 

Any information on what to do with this hard line would be greatly appreciated.

Is there pressure running through it, should I run it with the rubber cap for the being or could it cause other issues?

 

Thanks for the help fellow Z-enthusiasts!

Edited by Sanchez
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You are starting from waaaay behind.  That's the coolant hose from the radiator outlet to the water pump inlet that you have your finger on in that picture.  Nothing at all to do with fuel.  No offense, but you need to be careful before you start messing real fuel lines.

 

Fix the fuel fill hose problem first.  It's essentially in the cabin with you so any leakage at all is raw fuel smell.  Don't mess around in the engine bay until you spend some time studying.

 

" I also found out that the lines from the fuel fill to the tank leak when slightly overfilled and I am correcting that now."

 

Good luck.

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The line you are pointing to looks like the fuel return line. This was originally connected to a line in the fuel rail on the head. This is not absolutely required but is does help keep the fuel in the lines cool by circulating fuel through the lines and fuel tank. If you are not going to use it again make sure the other end where it connects to the fuel tank is disconnected and the tank fitting is well capped. The abandoned line can be left open, removed, whatever without any problems.

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Thanks for the outline, it was a bit of a confusing photo.

From what Beermanpete is saying I should be able to trace it back to the tank, disconnect it at the tank, and seal it off well. Or is there any benefit to using the fuel return with an electric pump and how would I go about doing that since the previous owner deleted the stock fuel rail and ised fuel hose instead.

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Post a pic of the fuel line going to your carbs also. So you just have the mechanical pump hooked up directly to the carbs? 

 

The benefit would just be that you have cooler fuel circulating, which if you get stuck in traffic much would help. You can trace the hardline back, but it goes to a rubber hose right before the tank, so you just put a cap on that and keep the hardline in place. There are probably some fumes coming from that line now but hardly any. 

 

You're best bet would be to try and find a stock fuel rail setup. 

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I forgot to specify, I have no mechanical pump cause I have an L28 with P79 head. I have an electric fuel pump at the tank with a splitter/pressure regulator (of unknown origin, but PSI is within 3.5 spec for carbs) and a fuel hose running from each outlet on that to a carb. I'll post photos later when I am done with classes.

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Was I being an ass?  I'm not seeing any fuel lines there.  The Snipping Tool and a red line would help.

 

How would the fuel return line be connected to the intake manifold, with a valve and some other fitting?  Not getting it.

 

The original fuel system on the carbed Z has a return line that loops back from a junction block in the fuel rail near the branch that feeds the rear carb. At the free end of the return line, near the fuel pump, a small metering orifice is built into the line (the steel section). This restricts the fuel flow sufficiently so the fuel pump can keep up with the bleed-off and the fuel requirement of the engine. Using an electric pump has no bearing on this as long as the new pump can supply enough volume of fuel at the required pressure.

 

My car has an electric pump at the rear and a small regulator near where the original fuel filter goes. The return line is connected in the factory configuration and it works fine.

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I forgot to specify, I have no mechanical pump cause I have an L28 with P79 head. I have an electric fuel pump at the tank with a splitter/pressure regulator (of unknown origin, but PSI is within 3.5 spec for carbs) and a fuel hose running from each outlet on that to a carb. I'll post photos later when I am done with class

 

Do you still have the factory fuel rail on the head and in use? If so, you could connect the return line (make sure the end at the tank is connected and the hose is good). Also, the regulator should be reasonably close to the carbs. Mine is on the inner fender near where the original fuel filter goes and it works well.

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