I recently put a 2 core radiator (CSF - Heavy Duty) in my XJ and its not cooling they way I expect it too.
I live in Las Vegas, NV and the temps here in summer are consistently above 105. The temp of my car at idle is in between 200 and 210. Normal driving will get my temp up to 210 maybe just a lil bit over like 215 at most. Highway driving will get my jeep to 225-230 and up a mountain will hold steady at 235. If my jeep hits 240 then I red line. I have not owned a jeep before and am not aware of the normal operating temps. Does this look normal??
I just expect putting a 2 core radiator to do more than that. As I read on other peoples XJ's some dont ever get above 210 with a 3 core radiator. So I would expect my XJ with a 2 core to never get above 220.
I dont like the thought of having to replace my head gasket but will if I must. I will add though I do not have any loss in power and my oil and antifreeze are still the same color. Another wards they arent mixing. I recently replaced my T-stat again and found that it was stuck open so i replaced it. I have not red lined since then and the temps I stated are after the T-stat was replaced.
Any help would appreciated....I have been struggling with this all summer!!

 

Water pump and fan clutch?

 

I'm kind of a newbie but until someone else checks in, did you burp your system after that thermostat installation? Also, did you make sure the thermostat was oriented the right way? Some thermostats have tiny holes to help burp the system. Might also be the fan clutch, but I don't know about those myself. Hopefully someone wiser than I will drop in with some better advice.

 

the fan clutch can go bad and the fan stops it form cooling. when the air passes those veins at a certain speed on the clutch it stops spinning, the car cools more efficiently when you pass a certain speed and there is no need for the fan at that point just natural air flow. If the fan keeps spinning because the clutch wont release then you will(can) run hot.
Do you have a shroud and if you do is it broken? that is a major part of the fan pulling air through the radiator. Get one or replace it if it is broken.
That is if all the above suggestions do not work. good luck! and let us know what fixes it.

 

@djb383
Water pump is like 2 years old so it is fairly new. When it starts to go bad there is usually a weeping hole and there is no antifreeze coming out of it. So I assume it is working correctly. I replaced my fan clutch and there was not a difference in temp.

@Bobisawesome
How is the thermostat supposed to be oriented? I just plopped it in there and seemed to all work okay.

I did not have a fan shroud because it broke so I replaced it awhile ago and it has made a difference but I still hit 235 which to me isnt right.

 

Just B/C your water pump is not leaking does not mean it is working as it should. I have seen some of the cheaper water pumps where the impellers get corroded or where the impeller gets deformed/broken to the point where it is not moving the coolant efficiently. Also make sure all the air is bled from the system and make sure your clutch fan is workin properly

 

I've seen a water pump with the blades completely rusted off even in an xj... but i don't think that can happen in two years

 

depends on the quality

 

Alright cool. Looks like I will be checking out that water pump after all. Also my oil gauge isnt stationary fluctuates from high to low. Not sure if that means anything...

 

It was from autozone...if that tells you the quality. haha

 

U say overheats at hi-way speed.....r u getting enough air around the winch and thru the rad? Big tires, high ambient, lack of air flow.....those can be a tuff combo. I doubt where u bought the pump makes any difference.

 

The entire grille is exposed. The bumper I bought sits far enough down that it doesn't impede the air flow.
Is there a "proper" way of getting the air out of the system? I have let the car just do its thing. I have this radiator cap that I can depressurize the system. It send the excess antifreeze to the reservoir and I do see little bits of bubbles. Really tiny ones though.

 

clutch fan still applies when high speed driving ,check it or just replace it anyway

 

tiny bubbles coming from the hose into the bottle ????????? while running lever on cap down??????

 

I just replaced the fan clutch. It runs just fine.
Tiny bubbles happen after I run the jeep and pull up on the lever on the radiator cap.

I have a question...I just took off my auxiliary fan sensor and there just a little bit of antifreeze coming out. Does that mean there is still air in the system? I figured that it should gush out as if that enitre cavity is filled with antifreeze.