03 Liberty Freedom Edition Overheating

[dalbertyjr]

Just had the motor rebuilt because overheating caused the head to warp and blew some rockers, that was 79K. New motor is now at 103K and overheating. Coolant was low and started to overheat at idle and then while driving... topped off coolant in overflow after cooled. Ran great for 45 minute ride home from work, and then 1/2 way back to work next day and then started overheating again. Overflow is filled, no leaks showing anywhere...

 

[CzarKJ]

Correct coolant? Is your E-Fan working?? That would be my bet.

 

[streetglideok]

Just had the motor rebuilt because overheating caused the head to warp and blew some rockers, that was 79K. New motor is now at 103K and overheating. Coolant was low and started to overheat at idle and then while driving... topped off coolant in overflow after cooled. Ran great for 45 minute ride home from work, and then 1/2 way back to work next day and then started overheating again. Overflow is filled, no leaks showing anywhere...

Stop and go driving, or highway driving at the time of overheating? Have you visually seen the radiator fan(electric one) turn on at the time of overheating? Electric fan is the primary fan, those with the mechanical fan, that is an auxiliary fan to the electric.

 

[dalbertyjr]

Ok, update... So Michigan weather is warming up, finally. Unfortunately the overheating issue as returned (and worse). The temp will cool down when driving, and if in park and the RPM's are raised will cool down also. The overflow is filled above the "cold level" mark. Thinking thermostat or possible air lock? Will probably replace the thermostat this weekend. Sound like a plan?

 

[02blue]

May want to check the water pump too. T-stat or bad WP = bad flow at low RPMs.

 

[dalbertyjr]

Water pump was just replaced a couple months ago (ya, still could be bad tho)...

 

[TwoBobsKJ]

Water pump was just replaced a couple months ago (ya, still could be bad tho)...

Are you using HOAT coolant? The "universal" stuff is killer in these engine - it will erode the impeller on the water pump and create sludge in the cooling system.

You can get HOAT-compliant coolant from the dealer or get Zerex G-05 from NAPA.

Bob