Fuel lines

This is the place to discuss NON-diesel engine and driveline modifications.
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Location: Jacksonville Florida
Isuzu vehicle(s): 1992 Isuzu Pickup 2.3L

Fuel lines

Postby korbin22 » Tue Feb 20, 2018 12:34 pm

So this might be a dumb question but I am very confused. I’m putting in a Weber carb and replacing the mechical fuel pump. What I don’t understand is why is there two fuel lines suppling the carb?? One from the vapor canister and the output on the mechincal fuel pump? From what I understand about the fuel pump is there is an input from he tank, an return that goes back to the tank (both connect back to the fuel lines under the car) then a drain line which leaks oil is the is failure and an output which o don’t understand where it goes? I would think it just goes to the fuel inlet on the carb but what about the one from the vapor canister? The one comes from the tank into the vapor canister into the carb. That’s how it was connected on the old carb. But I don’t remember where the mechincal output one connected. Someone please help my head hurts :?

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Isuzu vehicle(s): 1992 Isuzu pickup 2.3 carb

Re: Fuel lines

Postby Quahlity » Sun Feb 25, 2018 12:00 pm

There is one hose that just hangs down. It allows the other side of the diaphragm to not be sealed, while not allowing water/dirt in. If oil is leaking out of it, then it's good you are replacing it.