Hi all,

My 2002 Liberty (3.7l) overheated on the way home from work the other day. I assumed thermostat and so replaced that. Didn't help.

Now, the temp will rise to normal and stay there for a while - about 10 minutes or so - and then spike rapidly up. When I got home from my test drive last night, my radiator fan was not on when it clearly should have been. I gave it a whack on the motor with a wrench and it started up.

So, I'm thinking job 1 is likely to swap out my fan. But I'm looking for other suggestions. Where would you start? Bad relay? Blocked radiator?

Thanks,
Kris

 

It sounds like you're on the right track, if whacking the fan motor started it up it probably needs replacing. If it overheats again turn the heater on full hot, full fan. If that does not help I would be looking at a water pump. When you change the fan motor, change the relay at the same time. post what happens.

 

Thanks for the replies.

Once I was able to get a better look at it, I could see that the radiator had sprung a leak. So I replaced both the fan and radiator, and everything is working properly now. :)

 

Excellent news.
I just want to add that on the KJ's you will find that the Mopar replacement rad will be the longest lasting solution. Often by the time the rad is due, so are the hoses & 195 degree thermostat.
The Mopar thermostat has a built in weap hole, to assist in air bleeding.
Mopar hoses are the highest EPDM quality and so are Gates. (same in serpentine belt EPDM)
When you engage the A/C the electric fans should engage, something to check for as well.