Need help with fuel tank wiring

I have a 96 XJ. The factory tank got dented, so I replaced it with an Aero Tank 32 gal aux tank. This tank dented and cracked.... so today I pulled a tank (pump assembly and everything) off a 93 XJ in the junk yard.

My 96 XJ has 5 wires on the fuel pump wiring harness and a different connector than the one on the 93. However two of the wires were cut and wrapped off when my Aero Tank was installed.

So I now have 3 wires going to my fuel tank area. I assume red is power, black is ground, and yellow is for the sending unit.

The harness on the 93's tank also has three wires. They are orange (maybe red?), purple, and black.

Can someone tell me if I am correct in thinking orange is power, purple is the sending unit and black is ground? Can I just splice these together and be GTG?

Also there is approx 1 gallon of "fuel" in the tank of the 93. It's been in the junk yard god knows how long and who actually knows what's in the tank. What's the easiest way to get this out of there? I tried tipping the tank over but nothing poured out, I assume this is because of the baffling.

There are some venting hoses on top of the tank. Where to do I install these??

One last thing. I want to test the pump before I install. Can I just hook up a power and ground source straight from the battery and see if it runs?

to drain the gas when i pulled my tank due to a huge dent i used a cheapo hand pump from autozone for $10 they also have the same pump at harbor freight for cheaper
http://www.harborfreight.com/multi-use-transfer-pump-66418.html
and there should be two hard lines that go back farthest toward the tank the vents both t together and go to the small one atleast on my 89 and for the wiring im not sure but you should be able to test the pump with power and ground off the battery real quick to make sure it pumps

I only have one small hard line to the tank (I assume this is for the vents), and the rubber line that fuel is pumped through that goes to the fuel filter.

Is the other line supposed to be a return? I don't have this, I think they may have removed it when the aftermarket tank was installed. Where does it go in the engine bay?

96 has no return line from the fuel rail.

GrimmJeeper said:

96 has no return line from the fuel rail.

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But the 93 does? So I can just cap the line on the pump and be gtg?

yep. I only know because my return line is broken and i went to look at a 96 being parted out to grab it, only to find that the 96 only has a feed line going to the fuel rail, no return line from the rail to the tank.

Thanks!

Any ideas on the wiring?

cant you just use a volt meter and test at the connector ??

nismo5 said:

cant you just use a volt meter and test at the connector ??

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I know what wires to use on my jeep I just don't know which wires to connect them to on the new fuel pump...

The 96 fuel gauge sender is suppose to be unique ($$$$) (FITS 96 ONLY!).
so be careful with it and might try testing it with the fuel gauge prior to install. Look it over good, if it might be possible to swap it to the other pump if you are changing pump assemblys.

(Might save those 96 parts for later, kinda rare!

96- 49 +/-5 PSI


Good Luck,
Orange

I really don't like that year--1996--too much odd-ball stuff for me.

That 93 tank/pump assembly was to operate a system at 30 and 39 psi, depending on available engine vacuum to the FPR.

Most (if not all) in-tank fuel pumps are lubricated/cooled by the fuel. Hooking up an in-tank fuel pump without fuel to run through it will only damage it. Although I don't know anybody personally that has had it happen, there were reports back in the 80s of in-tank pumps grenading when bench tested--could be urban legend, but then again it might not be.

So the pump from the 93 will not work on my 96? God dammnit.

I have the pump for my 96 in my aero tank still but I don't have the factory sending unit, just the one that came with the aero.

90Pioneer said:

So the pump from the 93 will not work on my 96? God dammnit.

I have the pump for my 96 in my aero tank still but I don't have the factory sending unit, just the one that came with the aero.

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Not 100 percent sure it won't work--if you pinch off the FPR return line with the 30/39 pump running the pressure can hit 95 psi damn quick.

Just not sure if it can deliver the proper pressure and volume for the later system, you will need to do some research. As the 96 is such a "B" system try checking specs on a 97+ to the 95 and earlier system.

Just didn't want you getting it all together and finding out it starves fuel on you.

Good luck.

Does anyone know if a 96 pump will fit into the 93 pump assembly bracket?

Could I essentially remove the 93 pump from the 93's tank and replace with the 96 pump? I only have the 96 pump not the sending unit or any of the brackets it attaches to.

I don't really care about the fuel gauge working or not...

Pretty sure you're going to need to get a 96 sending unit / the assembly containing the pressure regulator. Either that, or an external regulator that does the same thing... or get a 95 or earlier fuel rail, fuel pressure regulator, and return line.

If you find a 96 fuel sending unit, it should obviously go right in and the gauge will even work.

A 97 up tank, fill/vent tube, pump assembly, etc are a much easier swap into a 96 due to the returnless fuel delivery system (that's what I did on my 96.) Some wire splicing gets it working great except the level sender.

kastein said:

Pretty sure you're going to need to get a 96 sending unit / the assembly containing the pressure regulator. Either that, or an external regulator that does the same thing... or get a 95 or earlier fuel rail, fuel pressure regulator, and return line.

If you find a 96 fuel sending unit, it should obviously go right in and the gauge will even work.

A 97 up tank, fill/vent tube, pump assembly, etc are a much easier swap into a 96 due to the returnless fuel delivery system (that's what I did on my 96.) Some wire splicing gets it working great except the level sender.

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The junkyard I pulled my new 8.25 came out of a 96 XJ. I was going to take the tank out of it but it had a small dent. The one on the 93 next to it was perfect. I could of grabbed the sending unit for free out of the 96 if I wanted. I'd love to go back and get it but they crushed the jeep right after I left.

Damn, I hate that kind of luck

Fortunately 96s were the most common year EVER for the XJ, they made nearly 300 thousand of them. I'm sure you can find another one pretty quickly. If your area is like mine it may be badly rusted though. I couldn't find a non rusted sending unit so I ended up paying 50 bucks for a 97+ tank, sending unit, pump, etc etc and did a bit of head scratching while installing it.

kastein said:

Damn, I hate that kind of luck

Fortunately 96s were the most common year EVER for the XJ, they made nearly 300 thousand of them. I'm sure you can find another one pretty quickly. If your area is like mine it may be badly rusted though. I couldn't find a non rusted sending unit so I ended up paying 50 bucks for a 97+ tank, sending unit, pump, etc etc and did a bit of head scratching while installing it.

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That I did not know! It seems like 96 XJs (even 95s for that matter) are near impossible to find in my area (Oregon). All I ever see are 86-90s, 93s, and 97+ XJs. Another wrecking yard near me has the sending unit out of a 96 XJ for 50 bucks but I'm trying to repair the jeep as cheap as possible and it's hard to justify spending 50 on something I could have gotten for free last Monday. I could also use that 50 bucks towards getting my Aero tank repaired, which I was quoted 200 on.

As a general rule I only see the years I don't need in the junkyard. I saw a bazillion 96s (literally, at least 3 of the 15 in the XJ row) at my local yard a few months ago, when I needed absolutely nothing off of them. Same thing happened when I was looking for a non broken 97+ header panel and some color matched 97+ fenders, it took me like 3 or 4 months to find those.