Fellow ARFcommers I seek your help. I may not be the best mechanic but am very much a diy'er.

I bought this 93 Cherokee as a wheeling toy and havent been able to get enjoy it and its killing me.

Idk if these problems coincide or not.  Im not as worried about burning oil as I am overheating.

These plugs are laid out in order left to right is 1 - 6.  2-4 look a little lean maybe from best google has told me.  They all look fouled and have some nasty build up on them.



Then I ran a compression check.
1. 125
2. 135
3. 145
4. 150
5. 135
6. 125

I performed a flush. I've replaced the water pump (correct directional flow), radiator, all hoses, fan clutch, efan switched on, rad cap (×2), thermostat (×2), and temp sensor (x2).  Everything is OEM parts.  I dont believe there is air in the system as the hoses have some pressure to them.  No catalytic converter to be plugged.

Give me some ideas before I sell this thing at a loss please!

Is it burning coolant? Over boil the coolant catch can? Possibly have a head gasket out of it?

Check for a cracked head. Could be intake gasket too causing lean condition in those cylinders.

Tell us how the temp needle behaves. Does it creep up steadily all the way into the red? Does it creep up and stop at some point? Does it creep up at idle, then return to normal once you start driving?

Considering the list of parts replaced, are you sure you are overheating?

Do you see coolant returning through the boil over tube? Have you tried verifying your block temps with an IR thermometer?

XJ has 2 temp senders, what is the part number of the one you replaced?

Or, find a known good, inexpensive mechanical temp gauge and hook it up to check the current gauge.
It might just be an instrumentation problem.
Is it overheating at idle, at speed?
If it's not the gauge, you can begin checking if it's an obstructed cooling system, collapsing lower hose, bad thermostat, bad water pump, fan problem, etc.

With lean running engines and unleaded fuel it's hard to read plugs nowadays.  Plug six looks like it's burning oil and maybe one too.

Rent a pressure tester for the cooling system. The XJ needs to maintain pressure to run at 210. If you have an air leak in the head, overflow bottle or another place the coolant will boil and run hot.

I forget what pressure they need to maintain.

The only other thing I can think of is the fins in the radiator are the problem. How many times did you flush the system? Did you use a flushing agent? My daughter jeep had the same issues and I had to flush it twice to stop the overheating. If that does not work I would replace the radiator.

If you are burning oil do a compression check along with looking at the plugs. Could be the rings. Read you did that


Is it throwing any codes for you yet?

Any oil in the coolant?

Which OEM rad did you purchase? The HD/max cool rad (MOPAR 52080104AC) is the only one worth a damn. How hot is it running?

Thermostat installed in proper direction?
Thermostat with the little weep hole in it to get all the air out?
When you replaced the bottom hose did you transfer the spring that keeps the hose open from the old hose into the new one?
With all you replaced & if all is working properly, If it's not something simple like above I'd check the head/gasket, start by looking under the oil filler cap for gunk.

If it is smoking white smoke out the exhaust that's is coolant. You have cracked head block or bad head gasket. If it has a cracked head or block bad or head gasket .You could have pressure going from the combustion chamber back into the coolant system causing coolant to flow out of the system.
Sounds like you replaced everything.Some 4.0 can get air in the system and cause problems. Wait till its cool and pull off small hose at thermostat and use a funnel to fill the coolant.
What I would do is buy a  laser thermometer at harbor freight and check the upper coolant hose and lower hose to make sure the coolant system is working correctly. You can also use on the radiator efficiency and exhaust manifold to check cylinder efficiency. Also make sure the fans come on at the correct temp.
If it is something major it would fall in this order head gasket, cracked head cracked block. If it is a head gasket on 4.0 it is usually leaking coolant on the out side of block.

Any update op?