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Project CRD MJ is born:

Yeah I know they have the big VM on them but weren't they basically a part of Fiat?

Keep in mind VM has been around awhile, and it wasn't untill recently that Fiat had any ownership of them.

That said even with Fiat ownership its not as if VM is just making Fiat designs. While I would be surprised if there was not any sharing of technology between Fiat and VM the VM designs remain in house.

Calling a VM engine a Fiat engine is really a misnomer.

Sure the engine was made by a company that is now majority owned by Fiat, but in that way I could say its a Penske engine since it was majority owned by Penske when it was made.

But its not a Penske engine, nor Detriot diesel, nor a Fiat. Just a VM Motori.
 
Finished installing the Chevy drop shackles. I got about an inch of lift out of them, I have one higher hole on the shackles I could use, but it won't give me much more lift.

This was the set I picked up, I am pleased with the quality for the price.
https://www.amazon.com/gp/product/B0106NWAJY


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MJ shackle top(which is longer than an XJ shackle)
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The width is a little different. I used giant cresent wrench to bend open the frame side shackle box, put the shackle in, and then bolted it tight. If I were a more patient man I would have pulled the bushing out, shaved down the width of the metal sleeve, and then bushing to make it the correct size.

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Likewise the other end is a little large, I picked up a couple of fender washers to take up space and then bolted it tight, again the nut and bolt pulled it closed some.

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Installed in lower position:

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How it sits now:

About 20" between flare bottom and wheel center. Height is OK. Might end up moving the shackle up once springs settle some.
 
Messed up the last part of that update.

Here is where it sits now:
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Before, with old springs, stock shackles, and SUA d35, and a heavy wildernest on it.

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I finished cutting off the old bracket and I got the new one trimmed to fit.

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I finished cleaning up the floor with the wire wheel and flap disked the area where the bracket needs to be welded down. I'll hit them with some copper weld through primer before welding, then follow up with seam sealer and POR15.
 
I opened up a tube of seam sealer, I had the option to buy brush on or caulk tube, so I went with the black caulk tube. I think I might order some of the brush on and see how it works, I'm nut sure the caulk gun method is always the best for what I need to do.

This image has black seam sealer on black por15, so its a little hard to make out, the short is there is a patch panel, por 15 over the area top and bottom, and then seam sealer over the weld area. The seam sealer came out in in long strands from the tube, so I spread it around evenly with a wood paddle to flatten and smooth. It seems to cover pretty well and the consistency and rubber pliability look good long term. Its a urethane product so it should hold up well long term.

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I dug the body harness out of the mess of stuff in the bed, I need to make some modifications in the rear section. The white plugs in the lower right of the image are usually behind the plastic which is under the spare tire carrier. These plug into the turn signals and factory wiring harness for trailer lights.

The MJ uses a different tail light setup than the XJ - its the same as what the XJ wagoneers had. This is more what trailer lights are like, or older vehicles. So the brake and turn are combined into one bulb.

I need to do some rewire work, including what I will do for trailer lights, and shorten the wiring to sit in the cab as those connectors are not weather rated. Right now I am planning to put them in the drivers rear void space behind where the stock rear speaker sits. Then I will tie that in with the factory plugs to the MJ rear harness that exits through a rubber grommet in the floor.

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Freerider came over and helped me burn on the seat brackets. Note the copper weld through primer I put down. It's a conductive primer so that you don't leave something as bare steel once you weld over it.

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After that I cleaned the floor with Acetone and got to work with the POR15:

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This is my next project, its the TJ cluster I am using for my MJ, I had to order some more equipment for this unit. The 02-06 TJ and 02-07 KJ similar years of WJ have no external eeprom, so the method is a little different.



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I'm enjoying this but the pictures are huge!
 
I'm enjoying this but the pictures are huge!

Understood and agreed, every other forum I post on will auto size pictures for your browsing convenience.

I was posting them as links because they are so huge, but a moderator edited my post and turned them into image tags instead. So now I post them with image tags, despite the hard to view size.
 
Got the fuse box in place today and started laying out the interior harness's, The dash harness's and engine bay are easy enough to deal with since they pretty much sit in the same place for the MJ as the XJ. However the body harness is a little different, today I placed it in the cab as is and didn't like how it was working out since the harness was meant to work with the 4 door XJ.

I stripped out the rear door wiring for the courtesy light and power windows, as well as the rear overhead light wiring. I still need to pull out the speaker wiring, rear wiper, and defrost wiring. I also then need to figure out how to arrange the remainder of the rear light wiring. the plugs used at the back of the XJ behind the spare tire will reach part way, but are not weatherproof connectors so they really shouldn't be used under the bed as-is.

I stripped the harness wrap bare so I could move some things around, but I am attempting to avoid a million splices in the harness.

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I will need to do some more testing in the future where I read through the OBDII port with a scanner to show what PSI to oil pressure sensor is seeing, and how that translates to the position on the TJ guage cluster. The TJ cluster is reading oil pressure through the PCI bus from the ECU, and then displaying that as an analog value. The question comes up as the the calibration, when it read "half" what PSI was that? When it went higher to 3/4 what PSI was that?

If you noticed the oil pressure gauge is the only one that does not have any units shown. This is because on the 2002+ TJ the oil pressure gauge is basically just an idiot light! The sensor on the newer TJ is a discrete, meaning it is either open or closed. In theory, when off or no pressure the switch is open circuit, and then when the engine is on and oil pressure is "good" it is closed. This way if your oil pressure drops below "good" or if it fails it should go open circuit. What the TJ ECU does is read this open or closed switch and send a value to the cluster. So the TJ cluster reading from the ECU only sees 0 PSI/bad, or X PSI/good. This means that on a stock TJ the oil pressure gauge either shows zero, or middle. Since the gauge is then basically just an idiot light they removed the units of measure.

However since the CRD ECU does read an analog pressure from the oil pressure sender the REAL psi is transmitted over the PCI bus, and since the TJ cluster is reading a real analog value it drives the gauge accordingly. The only thing left for me is to determine exactly what pressure the middle means, and exactly what pressure the high means.

I am working on a way to read the calibration from the processor onboard, which may allow me to change the scaling factor on the gauge. Likely that will be much further along, I'm just happy the Main functions, fuel level, coolant temp, RPM, and presumably speed all read correct.

In final form this will be wired into the normal dash wiring for the cluster for all functions such as turn signals, lights, 4wd indicator, etc, leaving the obdii port completely open like factory.
 
My coworker came over last sunday to use my pressure washer on his newly acquired wildernest to get it cleaned up, I decided it was a good time to open mine and take a look inside the back of the MJ........I'm find all sorts of parts I forgot where back there.


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Fun times ahead! Looking forward to having both MJs out and be camping!
 
Tested the TJ gauge cluster finally!
https://www.youtube.com/watch?v=xpO4isRTThs

However I thought the KJ plugs were the style I needed but it turned out they have more pins than the TJ, so I need to find the same connector type but with fewer pins to fit the TJ cluster.

Grrr, back to the junkyards to raid 15 year old Chryslers.


I will need to do some more testing in the future where I read through the OBDII port with a scanner to show what PSI to oil pressure sensor is seeing, and how that translates to the position on the TJ guage cluster. The TJ cluster is reading oil pressure through the PCI bus from the ECU, and then displaying that as an analog value. The question comes up as the the calibration, when it read "half" what PSI was that? When it went higher to 3/4 what PSI was that?

If you noticed the oil pressure gauge is the only one that does not have any units shown. This is because on the 2002+ TJ the oil pressure gauge is basically just an idiot light! The sensor on the newer TJ is a discrete, meaning it is either open or closed. In theory, when off or no pressure the switch is open circuit, and then when the engine is on and oil pressure is "good" it is closed. This way if your oil pressure drops below "good" or if it fails it should go open circuit. What the TJ ECU does is read this open or closed switch and send a value to the cluster. So the TJ cluster reading from the ECU only sees 0 PSI/bad, or X PSI/good. This means that on a stock TJ the oil pressure gauge either shows zero, or middle. Since the gauge is then basically just an idiot light they removed the units of measure.

However since the CRD ECU does read an analog pressure from the oil pressure sender the REAL psi is transmitted over the PCI bus, and since the TJ cluster is reading a real analog value it drives the gauge accordingly. The only thing left for me is to determine exactly what pressure the middle means, and exactly what pressure the high means.

I am working on a way to read the calibration from the processor onboard, which may allow me to change the scaling factor on the gauge. Likely that will be much further along, I'm just happy the Main functions, fuel level, coolant temp, RPM, and presumably speed all read correct.

In final form this will be wired into the normal dash wiring for the cluster for all functions such as turn signals, lights, 4wd indicator, etc, leaving the obdii port completely open like factory.
 
I made some progress on the TJ gauge cluster, I cannot seem to program less than 1000 miles, I suppose thats close enough to zero? I was just really looking forward to seeing it run up from zero. I might keep playing with it, I also want to figure out to reprogram the VIN.

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