bucketheadben

I'm having an issue with my project MJ. Let's start with its history first. It's a 99 Cheromanche. I've pulled everything from my old 99 XJ and stuck it in this MJ. Image Not Found In order to keep the fuel tank in the stock position, I swapped in the H.O. fuel rail, injectors, lines and pump. The problem is whenever I try to start it; it takes about 5 times before it will fire up. Once it fires up, I have to work the gas pedal until the idle smoothes out or it will die. After about a minute of that, it will idle on its own and run fine. At this point I can kill it and start it back up with no problems. I just pulled and cleaned the throttle body and sensors on it, but it didn't seem to help. Any suggestions? Thanks Ben

There are some good looking bumpers in here. I got some pretty good ideas from them, even an idea of what color I don't want to paint my bumper. :D

Thanks Pete. Lots of good ideas in there. Do you guys have any pics of your mounting plates like 89eliminator? Ben

The MJ's wheels are turning under it's own power again. I've got the mj fuel tank in it's stock location thanks to a few guys here on the forum. viewtopic.php?f=2&t=14996 Now that it's been running, I was able to charge up the a/c and freeze out that little cab. :D I've got a few things left on the list before I can start driving it. Then comes the fun stuff. I can't make up my mind, 33's or 35's?

Hey guys, I'd like to get some ideas on rear bumpers. Post up your rear bumper pics and mounting plates. Thanks Ben

I just finished splicing in the wires for the fuel injectors. The fuel rail is full of gas and I'm getting spark to the plugs but it will not start. It turns over and it sounds like it's trying to fire but all it does is sputter while the starter is engaged. Any ideas? Thanks Ben

Well, I'm almost there. Since I can't find a MJ H.O. sending unit, I stuck the Renix assembly in the tank. So far I've got the tank and pump back in it's original location, installed a fuel filter, H.O. fuel lines, fuel rail and injectors. I've spliced the wires so that the fuel pump adapts to the 99 harness. I've got the pump working and the fuel rail is pressurized. Now all I have left is to splice in the H.O. injector wiring harness and fire it up.

Sorry, I should have said "fuel pump assembly." That is what I ordered from autozone. I've checked autozone, advaced, napa and pepboys for a MJ fuel pump assembly, but they all have the same part number as the XJ.

Oh, I forgot to mention that the problem with the fuel pump from auto zone was that it would not mount in the MJ tank. The pump would hit the slosh tray. The renix pump that I have goes into the tank at an angle and into the tray. The auto zone one just goes down and hits the tray.

Well I had a good day at the junkyards. I scored wiring for the H.O. injectors, 2 fuel lines, mounting hardware for the tank, the locking ring for the pump and the carpeted interior panel behind both seats. All for $20. I already have the H.O. fuel rail and injectors so now I just have to hook it all up. On the down side the fuel pump auto zone order was wrong. I had the check and it has the same part number as the Cherokee fuel pump. Does anyone have the part number for a 91-92 Comanche fuel pump or do you know where I can purchase one? Until then I'll hook up the renix pump I have and get it running for the time being. One other question. The 99 fuel pump has 4 wires, and the renix has 3. How many wires are in the H.O. fuel pump? And does anybody have wiring diagrams so that I can splice everything together? Thanks again for all your help. Ben

I just went out and looked at the renix pump. The return line dumps in to the tank. It doesn't got into the pump. If the H.O. pump is plumbed the same way, would it vapor lock? :hmm: Ben

Nope, no return line. I'm sure of it. It has one fuel line and a vent line. So should I just cap the return? I will be buying a 91-92 pump tomorrow. I just had a renix pump handy so I was using that as a reference. Thanks again for the help. Ben

That's excellent news guys. Thanks. I do have one other question. I was looking on the the Renix fuel pump and it has a return line. Should I just cap it off? Ben

Is that all that I have to do? That is too easy! :bowdown: I thought they ran at two completely different PSI's.

I need to use the 99 fuel pump and it won't mount in the mj's tank.

I've swapped the entire drivetrain from my 99XJ into my MJ, now I have to figure out how to get fuel to it. Id really like to keep the tank in the stock MJ location, but he XJ tank will not fit naturally. So I'm wandering if anyone knows the measurements of a TJ or Grand Cherokee gas tank. Maybe one of those will fit. Or if there is no other option, I'll put a fuel cell in the bed. Has anybody been faced with this issue or have any ideas. Thanks Ben

The dash was much easier than I though it would be. There were 2 mounting brackets that need to be removed from the XJ. One that will hold the steering column and the other one was over the tranny hump if I remember correctly. Just drill out he welds and mount them in the same spot on the MJ. After you do that, there are a few holes than need to be drilled out for the HVAC ducting, cables and steering column. For the seat mouts, I have cut out the upside-down channel brackes from the cherokee and plan on welding them to the floor just like in the XJ. I have the semi-mocked up that way now and the look like it will work. Ben

On the door catches, I drilled out the back bracket for the old catch and put the new one in it's place. On my 99XJ the bracket was just held in my a clip. If I remember correctly the old catch hole lines up with the top hole for the new catch, so you only have to drill one hole. Hope this helps. Ben

Well I got off of my lazy butt an took some more pics as it sits. Image Not Found Image Not Found It now moves under it's own power, but is still along way from being street legal. My biggest problem will be trying to figure out what to do with this gas tank. Image Not Found Once the tank is finish I'll be on the downhill slope. All that's left is little odds and ends like welding up seat brakets so i can finish the interior, installing a rear sliding window, e'brake cables, an a few other things.

Here you go. Let me know if you want another. Image Not Found

Here's a few updated pics. Image Not Found Image Not Found I'll snap more recent ones soon.

I will be swapping everthing posible from the XJ to MJ(hood and doors included.) I just left the hood and doors on the MJ to keep as much rain out of the cab as possible since i'm doing all my work outside. Thanks for the advice on the foors.

Hey guys it's time for and update. I'm now driving the White XJ. I have also stripped all of the interior out of my 99XJ and have stripped down the MJ to the frame/cab. Image Not Found Image Not Found I have also cut out all of the rust on the MJ's floor, then coated it with a rust converter and primer. Now it sits waiting for a floor. I havn't decided it i want to build a new floor out of sheetmetal from my work(HVAC shop) or cut and weld the floor out of the 99XJ. What would you guys suggest? Here's a few pics of what i'll be tackling in the next few weeks. After the floors i'll start with the drivetrain transplant. Image Not Found Image Not Found Image Not Found

I think i found the problem. It was not the pump because i wired it directly off of the the battery and it pumped. So i disconnected the outlet hose on the pump so i could see if it would pump when i turned the key. Nothing in the 'on' position, but when i started it i got fuel. So after checking the ceramic resistor again i found the female connectors were in rough shape and i did not had a good connection when i tried to jump the wires together the first time. So i cleaned them up real good and shorted the wires directly together and i got fuel to pump in the 'on' position. So I hooked the hose back up, started it up and drove it around for about 15mins and no problems. I'm pretty confident this will solve my long starting problem since it wasn't priming in the 'on' position. I think I've read before that some people have just left the resistor bypassed and have not have problems, or am i remembering incorrectly? Does it do anything other than quiet down the pump. Thanks for all of the help.

Sorry, I forgot to mention that i changed the fuel filter, plugs, wires, cap and rotor button when I bought the XJ. I just finished pulling and cleaning the IAC and using Sea foam but it doesn't seem like it did anything noticable. I actually left it running while i was washing my hands and when i walked outside it was not running any more. So i pulled the cap on the fuel rail and pressed in the shcrader valve and got what i thought was very little fuel. I'd say no more than a couple tablespoons of gas. So i'm realy leaning towards the fuel pump. Does anyone else agree. Ben