Picked up my 99 sport for 900$ seller told me it was a bad headgasket and his mechanic was going to charge him 3,500$ ouch!! I've worked on cars for 13 years and thought it was strange. So limping it home I new it wasn't a head gasket simply due to the way it overheated. Got it back to the shop and drained the coolant/stopleak/rust and popped the thermostat out. Well it wouldn't open! Victory I thought haha well after a day same thing. But now only at stops haha!
Removed the water pump and found the blades missing! Victory again I thought! New water pump and flushed the system. After another day I'm back to overheating on the highway! Well I know from seeing it stop leak is the worst thing you could ever put in your cooling system! New radiator and electric fan to replace the clutch fan solved it!

 

Yea rebuilding the cooling systems on these vehicles is a right of passage to XJ ownership. I did everything on mine all at the same time: water pump, fan clutch, radiator hoses, t-stat, and I also replaced the belt while I was in there. Radiator was replaced by the PO a few months before I bought it.

When I bought it, mine would have temp creep at stop lights. The temp would climb up and the aux fan would kick on and bring it back down. Now with the system rebuilt it just sits a hair below 210 most of the time and the aux fan never runs.

 

Yeah she runs a lot cooler now can't believe how much stop leak was in it haha

 

LOL, the cooling systems on these Jeeps are a common failure point if not maintained.

Stick around awhile and you will see about 3 new “help, I’m overheating” threads a week in the OEM tech section.

 

What electric fan did you mount in there?

I can't imagine why that old water pump wasn't still working! LOL

 

It was an 11 inch Hayden fan and put in an adjustable control relay. And haha yeah pump looked like a throwing star