Jeep overheating

[LibertyFever]

So mine is doing this as well. Just started were temp will go up to about 3/4. Today it did it on the way home, temp gauge showed it as 3/4 line, mostly when I stop, then started going back down. When I got home the water was boiling out, gauge showed in between 1/2 and 3/4..

Do you guys think its the thermostat? If so were is the thermostat located so I can change it. BTW mine is a 2005 Liberty 3.7.

I agree with J-Thompson that it sounds like your electric fan isn't working since the engine begins to cool when you're moving. Once upon a time I had a similar problem with my KJ's transmission. It would overheat but only while on the trail driving slow. My electric rad fan had burnt up.

The typical KJ has just just one rad fan a two speed electric one attached to the rad. The fan, it's relay or the fuse can fail. Unplug the rad fan and measure the voltages with the engine up to temp and the A/C one. The fan should be running then.

 

[Smeltn]

So I got in this morning and turned it on. Turned on the A/C then turned on the heat and the fan never started spinning. I had this problem a while ago where the fan would turn on, then instantly turn off, but after checking it later, it started working again.. I am so confused though, as I was thinking the thermostat, or waterpump, but with the previous fan problems now I am beginning to think it is the fan, if you guys think it could cause it to overheat like that. What about overheating even on the highway? I have had it do that on me?

So the fan not running will cause it to overheat like that?

Where do I check the fuses and relay located for the fan?

Anything else I need to check?

Also if it is the fan, how hard is that to replace? Is it something I can do myself?

 

[LibertyFever]

I have an 04 so I'm not positive where the fuses and relays are but I suggest you check under the hood within the power distribution box.

Have you unplugged the fan and checked it for continuity? I believe the center wire is the common and the outside wires are the Hi/Lo speeds.

Pulling out the electric fan is pretty simple, remove the top two 10 mm bolts and loosen the bottom two. It's a little more difficult in a KJ with the additional mechanical clutch fan. Often the fan gets plugged up with dust & dirt and only needs a good cleaning.

 

[LibertyTC]

In #43 TJKJ shows where the fan relay is .
http://www.jeepkj.com/forum/showthread.php?t=44134&highlight=electric&page=5
Under the hood right side, behind the battery,when you open the Power Distribution Center's fuse box there is a sticker inside the lid, with Descriptions of each fuse.
Note that further searches in this forum under fan, may indicate how to rebuild/cleaning the fan assembly and testing of the electric fan.