I recently had my cooling system on my 98 Jeep Cherokee power flushed, thermostat replaced, lower radiator hose replaced, and (at the recommendation of the dealer) the water pump replaced. Well, now the vehicle runs hot, and there was no problem before. Even when not overheating, the water temperature is much higher than it used to be, and the auxiliary fan runs most of the time. Any load on the cooling system, such as climbing a hill or being stopped in traffic for a while, will cause it to overheat.
The dealership says that the power flush knocked debris into the radiator and clogged it, and that the radiator needs to be replaced. Is this likely, or even possible?
Possible, but I wonder if there’s some air trapped somewhere in the system. I sure wouldn’t give them the $$ for fixing something they caused! Were there no problems before this?
No. If there were any blockage before or during the coolant flush, the flush machine would have built enough pressure to blow open the pressure cap. The first thing I would try is replacing the new thermostat. It’s not uncommon to get a defective thermostat right out of the box.
Tester
This is a long shot, but could the thermostat be installed incorrectly? At least test it if it is defective.
The cooling system seemed to work just fine before. Last summer, the upper radiator hose started cracking, so I replaced it and the thermostat (just for good measure). But I knew that the lower radiator hose was old and needed replacement also. But I procrastinated until two weeks ago when I took it in to the dealership and asked them to replace the hose, the thermostat, and flush to cooling system. There were no problems before.
It worked when you took it in and now it does not.
Take it back and make them fix it!
Defective thermostat or incorrectly installed thermostat came immediately to my mind also. I would also look into a new radiator cap, the pressure flush could have damaged the seal and its not holding pressure anymore.
A little off the subject, but you have just proven the fact that dealers are really not better (or worse) than independent mechanics, but if you checked, you will find out that dealers are almost always more expensive. Unless the work is covered 100% by warranty, don’t go to a dealer.