I just got a 1989 jeep comanche 4.0l 5 speed. The engine has 279,000 miles it runs good but overheats. I raced the thermostat water pump but no luck with getting it to stop. Any clue why.

I believe Jeep used the 4.0 inline 6 motors in the Cherokee up till 2001 and in the wrangler into the mid 2000's.

My comanche overheated when I incorrectly connected the heater hoses to heater core, swapped the two around all was good after that. If I remember right top heater hose off the thermostat housing ends up on the top heater core connection.