Brand New To Me 1990 XJ (build and Question thread)

wikun

Observer
Well I just jumped in head first today...I have long since been a lurker on this forum, so today IT finally happened for me. It was pouring rain here in San Diego, but I was too excited and the owner wanted it gone. 1990 Cherokee Limited 4x4 with the 4.0 ltr engine. The back story is that the owner thought that it needed major repair because of a heating issue. I knew that these jeeps have problems with their bottles, and was hoping that it was that. He popped the hood and said when it overheats, the coolant escapes in gasseous form and he pointed straight at the bottle. GREAT... It runs, drives and goes into 4hi and lo. So this forum is going to serve two purposes if you guys help...wink wink... My build forum for my offroad/expo toy and for questions. Pictures will come soon (still raining and dark, now) But first a question...Overheating...I know that there are two options...Convert to an open system, or switch the bottle and eep the closed. My question is the pros and cons of both, and also does anyone know of a place where I can get an aluminum bottle or something comparable? i think keeping the closed system would be best but correct me if I am wrong. Thanks to everyone on this whole website. I have been a member for almost 2 years and without the guidance on this site, I would be lost. Thanks and happy expoing. :smiley_drive:
 

BlueGerbil

C´est le gerbil plus bleu
Congratulations for your find! I had a ´90 XJ as well and loved it.

I´d buy a new radiator, new hoses and convert it to the new cooling system. AFAIK it has more cooling capacity. The 4.0 is a quite hot running engine and the stock cooling system is quite marginal, especially when the vehicle is built heavy, bigger tires, mountain roads...

Don´t forget to change the thermostat when it´s still the stock one - that´s a cheap part and gives some peace of mind and is another part which shouldn´t cause problems "out there".
 

bob91yj

Resident **************
Congrats on your find.

I vote for updating the cooling system. I had an '88 XJ, always had a new bottle and cap bouncing around in the back waiting for the one under the hood to start leaking. Wasn't a matter of "if", but "when".

I'd also recommend buying a round of underhood sensors for your engine, TPS, CPS, MAP, etc. It's not so much that they are prone to failure, but your engine uses Renix engine management. Sensors are different from Mopar HO version sensors, a little harder to find, especially in the middle of no where.
 

ExpoMike

Well-known member
I thought '90 did away with the Renix system. It wasn't the HO yet but I thought '89 was the last year for Renix.

Congrats on your new rig. Pics!!!!
 

BIGdaddy

Expedition Leader
Mine's a 1992 with an HO and open system just for reference. First or second year for a lot of things I think.

Pretty sure 1991 was the big change over from renix.
 

wikun

Observer
I am having trouble posting pictures....I now their are post on how to do it, but my search is turning up nothing....Any ideas?
 

wikun

Observer
DSC00632.jpg

DSC00633.jpg

DSC00636.jpg

DSC00637.jpg

I think I finally am getting it. They are a bit small, but I am learning. Here you go...Some jeep porn.
 

wikun

Observer
Today was all paperwork...Smog the vehicle (actually yesterday), Register with CA DMV, get base stickers, grocery shop with wife, and then stand in the rain and pressure wash and degrime the vehicle as best I could. Getting as much grime off as possible. Short term plans are :
This weekend is all about maintenance
1. Oil change
2. Coolant flush with new hoses, thermostat, clamps,
3. Diffs fluid and gasket replacement
4. Trans fluid and filter

Next weekend is transfer case
1. Chain
2. Fluid

And then the plan is start working on the toy aspect. Pics to follow as soon as this darn rain stops...:coffeedrink:
 

alexfm

Explorer
I like the rims you've got. It looks like you've got a solid plan too, so your headed in the right direction. Are you gonna replace the chain in the transfercase? I'd like some details on that. Which case do you have in your rig?
 

wADVr

Adventurer
Congrats on the new to you XJ. I started with the exact same year, model, trim, color XJ 10 years ago and still miss that jeep.

Convert over to the open system. Much easier to find parts for in the middle of nowwhere and is a much better performing/understandable system. I also had a '90 that I tried just putting a new bottle in and updating it but later found the open system to be the way to go in the end.

I will assume it has a NP242. Why feel the need to swap the chain? I personally would look for a NP231 in better condition.
 

Dirty_Jeeper

Adventurer
Good to see another XJ getting ready to leave the pavement. I suggest keeping an eye on Craigslist, Auto Parts section. I'm in LA but CL seems to always have some deals on sliders, bumpers, lifts, etc to be found. Might keep the wife happy as the build cost adds up fast! LOL!
 

Forum statistics

Threads
189,990
Messages
2,922,932
Members
233,209
Latest member
Goldenbora
Top