Cummins R2.8 97 TJ

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I spent my shop time today modifying my radiator support to house my intercooler. Maybe the grill goes in tomorrow, but I am on borrowed time because my daughter is due with my first grandchild, so at any minute the project goes on hold

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rasband

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I spent my shop time today modifying my radiator support to house my intercooler. Maybe the grill goes in tomorrow, but I am on borrowed time because my daughter is due with my first grandchild, so at any minute the project goes on hold

View attachment 335165

View attachment 335167

You should just mount the intercooler to the front bumper! 😂😂

Congrats on the impending grand baby!
 
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Grill assembly finished, intercooler is kind of permanent, welded straps top and bottom, I would need to cut the welds to get it out, but at least it shouldn’t fall out on the trail

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I got to try out a new tool today rolling beads on the intercooler tubing, worked great, but I found that I can't roll a bead on a tube that has been cut where a bend is. Unfortunately I no longer have access to a TIG welder since I just retired and I hate to buy one just for this project, but it could happen. I had to put a bit of a flex in the 90 degree fittings that come and go to the intercooler, but I think they will be ok. Next, I am fabbing up some radiator hoses, and I think I am able to modify the stock upper hose to work. For the lower hose I am taking two different hoses and cutting the ends off and then machining a piece of two inch aluminum tubing to join them together and in the center of the tube I will make a port for a air breather to route to the de-air box.
 
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Cooling system is plumbed, I was able to repurpose the stock Jeep radiator hoses with a few mods. Looks like driver’s fender fits, will test passenger side tomorrow. I don’t want to install them until I complete the wiring.

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I had to take a break from my project for a couple of weeks while my daughter was giving birth to my first grandson. I am back at it for a few days, fuel tank installed, fuel filter housing installed and best of all, the installation kit from Cummins got dropped off, so I might actually make some good progress now. On the to do list is drill a hole in the firewall for the wiring harness bulkhead, wire up the intellitronix digital gauges and start buttoning things up.
 

NashvilleTJ

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I had to take a break from my project for a couple of weeks while my daughter was giving birth to my first grandson. I am back at it for a few days, fuel tank installed, fuel filter housing installed and best of all, the installation kit from Cummins got dropped off, so I might actually make some good progress now. On the to do list is drill a hole in the firewall for the wiring harness bulkhead, wire up the intellitronix digital gauges and start buttoning things up.

Congratulations grand-dad. My first is about a year and a half, and I have two more on the way.
 
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Another day of work in the books! Spent the day wiring the intellitronix digital dash. Everything went well, soldered all connections and powered it up and everything worked except the oil pressure, just blank, no lights. I removed the tinted plexiglass cover from the electronics and now it works. Hmmm, then I looked at the black plastic panel that goes between the tinted panel and the led gauges and low and behold the space for the oil pressure was cut, but it was still there. Fixed! Installed the gps speedometer sending unit along with the gauges too. Took way longer than it should have, but connecting the 23 pin plug in the wiring harness for the engine was a PIA, finally got it. Installed the gas pedal and ran wires to the fuel gauge and oil pressure gauge and water temp gauge. Dug out a hot in run and crank wire from the ignition circuit and have a wire ready to tie into the Cummins wiring harness. I was very happy that a factory rubber plug in the TJ tub was a perfect fit for the Cummins wiring harness. I will try and post of photos of the digital gauge tomorrow, it looks cool. Only a couple of wires left to terminate in the cab and hook up wiring under the hood and it might be ready to fire up after adding some diesel to the tank. Ordered a Banks suction mount pod mount for the Murphy gauge because I can't find a good place to mount it. Need to wiring the relay for the electric fan, the grid heater and make a mount for the ECM and then it will be time to put the fenders back on! Getting close.
 
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Wildman

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Another day of work in the books! Spent the day wiring the intellitronix digital dash. Everything went well, soldered all connections and powered it up and everything worked except the oil pressure, just blank, no lights. I removed the tinted plexiglass cover from the electronics and now it works. Hmmm, then I looked at the black plastic panel that goes between the tinted panel and the led gauges and low and behold the space for the oil pressure was cut, but it was still there. Fixed! Installed the gps speedometer sending unit along with the gauges too. Took way longer than it should have, but connecting the 23 pin plug in the wiring harness for the engine was a PIA, finally got it. Installed the gas pedal and ran wires to the fuel gauge and oil pressure gauge and water temp gauge. Dug out a hot in run and crank wire from the ignition circuit and have a wire ready to tie into the Cummins wiring harness. I was very happy that a factory rubber plug in the TJ tub was a perfect fit for the Cummins wiring harness. I will try and post of photos of the digital gauge tomorrow, it looks cool.

Interested in how you like the Intellitronix digital dash? I have one that I picked up for really cheap off Ebay a while back but haven't decided if I'd install it or run my stock dash yet. With my V-8 swap I can run the stock dash but I'd always liked the look of the digital dash.
 
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Interested in how you like the Intellitronix digital dash? I have one that I picked up for really cheap off Ebay a while back but haven't decided if I'd install it or run my stock dash yet. With my V-8 swap I can run the stock dash but I'd always liked the look of the digital dash.

I don't know where the time went today, but the wiring continues. Harness wiring is complete, tach hooked up, wait to start light, emergency stop light as well as function switches for the gauges are set in the dash. Tomorrow IG should have the suction cup pod mount to install my murphy gauge. I had to modify the power distribution box to play with the intake are tubing and tweak the intake air tubing a bit. Passenger fender is on, ground bus bar is installed on the frame. ECM is mounted and grounded. Grid heater solenoid is wired and a test location is picked out. Starter cable is made and installed. Dash is buttoned up, accept I have two wires that I don't remember where they go, so I need to take some of the dash apart again to trace the wires. Tomorrow I install the driver's side fender, wire up the premier power welder and connect battery and grounds! Then it will be time to fire up the engine!!!!!
 

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I just purchased a Cummins R2.8 To swap into my 97 Jeep TJ. My main goal is low end torque and fuel economy mostly off road. My Jeep is mostly built, with the exception of the engine. If someone needs a good running 4.0, let me know it will be for sale soon. At this point I think I will pull the body off of the frame to do the engine install. It will mean tying up my two post lift for a little while, but hopefully not too long. The engine was supposed to show up on Fed Ex freight today, but I might be waiting 30-60 days for my adapter and motor mounts to show up from Quickdraw. I have decided to ditch my plans for retaining the A/C because I don't think it will be worth the trouble. My last engine swap was a 24v Cummins into a 1985 Suburban with NVG 4500 trans, NP 205 transfercase, D-60 front with detroit and 14 bolt rear with detroit, it was a cool rig. This one should be easier, I hope!

Interesting project. If you discover any new quirks of the 97 model along the way, let us know on the thread in my signature line.
 
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The Jeep lives again! I was disappointed last night when I thought everything was hooked up and ready to fire, turned the key and lights on the dash lit up and no starter engagement, WTF! I pulled the started relay and attempted to jump it and still no go. Hmmm. I thought about it for a while and went back out after dinner and ran a jumper wire to the solenoid feed from the relay and attached it to battery+ and the engine started right up! I didn't have the alternator charging, so the wire from the cummins ECU wouldn't work for my premier power welder modified cummins alternator, I needed a keyed hot. I went back out this morning and scratched my head a few times and thought since I don't have the Jeep ECM, maybe the starter relay isn't getting a ground signal. I cut the wire on the relay and ran it directly to the battery- and she works! Then I repurposed the relay for the fuel pump to give power to the alternator and all systems are go! I idled the engine for about 45 minutes to get it up to temp and test the electric fan and it came on at about 190 degrees. I really like the looks of the intellitronix gauges, I put the tachometer into 8 cylinder mode and it made the tach very close to matching the Murphy gauge, when it was in 4 cylinder mode it was way off, showing 1600 rpms at idle when it was really about 800. I still haven't driven it yet, probably in the morning. To the best of my knowledge everything electric is now working. I will try and post some photos from my phone in a few minutes. I ended up running 2.5 inch stainless exhaust pipe and straight piped it , it really isn't very noisy at all.
 
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I must have messed up the photo showing the clearance of the oil filter to the front axle with the suspension flexed, but I still had about 4 inches, so it should be good. Jeep ran great on maiden test run mostly in the hills, temp never got over 200 and cooled quickly once the electric fan kicked on. Bottom end torque is much better than the 4.0 and Jeep is much quicker accelerating on the road too. I have to park it for a few days to go visit my daughter, but then I can continue testing
 
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Is that oil filter location going to work?

Oil filter seems to be fine with a 4 inch lift, with driver side tire stuffed into the fender, I still had about 4 inches of clearance and right rear tire was almost off the ground, this is with the shortest Cummins oil filter
 
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