I have a 1996 4.0L 5spd manual XJ that’s running hotter than I’m comfortable with. It stays around 220-230 around town and goes up to 230-240 on the freeway. I live in a high desert and summer temps are often over 100F with low humidity. I need this thing to be reliable on solo missions in remote parts of the Utah desert with no cell service.

I replaced the entire cooling system already (water pump, thermostat, radiator hoses, heater hoses, heater core, fan clutch, electric fan, radiator). I flushed the system prior to doing this. The radiator is a stock Spectra unit from Autozone and I upgraded the fan clutch to the ZJ one that everyone talks about that sounds like jet on takeoff. No dice.

I was looking at the FF Dynamics aluminum radiator/3 fan combo for $500, but ideally I’d like to stick with a mechanical fan for reliability and also not spend so much. What are my best options here? Is there a good radiator upgrade that will work with the stock fan setup? I’m seeing mixed opinions on Champion and CSF radiators, not finding much on Cold Case though. Reliability is key.

edit: what about an engine oil cooler? Has anyone tried one?

 

I did all you did but I use a Champion 2 Row Radiator and it is working my XJ cool even on days that are 110 it runs under the 210 on the gauge .

 

How long have you been running it for?

 

About 3 or 4 years now with no problems , and I run the A/C a lot if it is over 80 my A/C is on ,

 

Champion all aluminum here, 0 cooling issues.

 

I would do the following before any "upgrades/down grades"

1: verify temps (IR gun, mech gauge, etc.)
2. Check coolant passages with a scope, make sure the engine is not all clogged.
3. make sure you are not running lean and timing is correct

 

one test to see if there is insufficient cooling capacity, ie inefficient radiator or clogged engine coolant passages is to turn on the heater with full fan

normally going down the highway should not overheat as fans etc are virtually irrelevant with all that airflow

if it overheats at idle or crawling, fans and other related items become more suspect

 

sometimes overheating happens even with a perfect cooling system. Things like an intake leak, bad sensors, carbon build up in head, clogged cat, bad injector, etc.. can cause over heat even with a perfect cooling Of course the temperature gage maybe off too.

 

All that, and blowing exhaust gasses into the coolant via cracked head or blown head gasket will also cause overheating.

XJs cool just fine in exactly your weather conditions with a properly working cooling system. If yours isn't getting the job done, something is wrong. An "upgrade" won't fix it. It might mask it, but it won't fix it.

 

I did some googling, and it’s kinda funny how polarized the stances can get on this subject. I agree the cooling system should be able to handle it, but it clearly isn’t. I’m not finding any leaks anywhere, compression is 145-150 psi on all cylinders, it runs fine, passes smog with flying colors, no codes, new Bosch O2 sensors, new-ish cat, 100% new cooling system. All I can think of is a bad sensor, rust in the engine, or maybe this engine has always run warm and it hasn’t been a problem?

Either way, I’ve completely gone through it. I’m about to install a Champion 2 row radiator today, we’ll see how it goes.

 

Using a factory stat?

 

Factory temp 195 Stant thermostat. I tested it in hot water before installing it.

 

Well, we have multiple members who live in climates like yours with zero problems. We also see a pretty steady stream of people who spend good money to "fix" their problem and fail, and then finally do the basics and discover what the real issue was.

 

I live in northern az and I get what you mean about heat. I recently swapped in a cold case 2 row, plus a fan switch. And I haven’t had any issues yet took it out wheelin 240 miles total on the day ac on entire time 100 plus outside. Family likes it cool so I made it work. Just my 2 cents.
I stay right around 210 maybe a hair above it when warmed up.

 

I live in Northern Arizona and have had many XJs and MJs with stock radiators, cooling fans and factory thermostats that worked just fine.