2004 Liberty running hot **SOLVED**

[mduclow]

Hi everyone, I have an issue with a 2004 Liberty (3.7) running hot, I would like to see what the guys that know these Liberty's have to say about it. I grew up building cars, mostly GM/chevy's, but don't know the Liberty's like some of you do.

Here's the situation:
Since owning the Liberty it has a low threshhold for running hot.
Shortly after buying this Liberty with 187,000 miles in 2020 my wife and I put an aftermarket motor in it. A new water pump, thermostat and hoses were done with the motor as well. As to the thermostat, these were serious Jeep guys recommended to me, so I can only assume it is a proper t-stat and installed correctly. Other aspects of how it runs supports a good t-stat and correct installation (maybe).

I have verified that the electric fan is working as it should. When the A/C is turned on the fan does come on, even if it is cold and has just been started. I have confirmed (over a 45 minute period) that the fan does cycle between low speed and high speed. It appears to cycle properly.

So the car now has 200,000 miles, with a new motor (7,000 miles), new hoses, new water pump, and new thermostat with the electric fan verified to work properly.

When I drive it without the A/C it doesn't get hot, much. In hot summer temps climbing hills (with speed on the pavement roads) it might get a little hot (5/8's or less) but will cool down fairly quickly. If I take it into the mountains and start climbing it will quickly (within 10 minutes depending on outside temperatures) start running hotter, requiring a stop to let it cool down.

If I drive it with A/C (summer temps obviously) it will run hot, and quickly run hot with any strain on the motor, like climbing hills. It will be bad enough I need to turn the A/C off and then it will start to cool down within a couple minutes and cool down to halfway on the gauge in about 7 or 8 minutes if there is no strain on the motor.

I feel the vehicle is not properly dissipating heat through the cooling system. I don't think I have clogged passages through the motor (new), I think all but the radiator is confirmed working properly.

I am leaning (heavily) towards the radiator being original (200,000 miles and now 17 years), clogged and inefficient.

Would the experts in this area please chime in and offer your 2 cents worth?

Thank you!

 

[turblediesel]

The experts will be along soon.

I do know that there's a hole in the thermostat that needs to be oriented correctly. There's a bleed ***** somewhere high on the engine to get all the air out. Folks have some trouble getting all the air out of these engines. If regular green antifreeze gets mixed with the proper HOAT antifreeze it gels and clogs. Is your mechanical fan engaging properly?

 

[mduclow]

I should have mentioned that yesterday I tried to burp some air out and it didn't burp anything . This was from removing the cap on the overflow (with the front at an upward angle). Additionally I lossened the purge valve, and it never stopped bubbling, even after an hour of letting it run, it never stopped bubbling. That is odd to me.

 

[JeepJeepster]

If it only overheats under heavy loads, my attention normally turns to the radiator.

 

[LibertyTC]

A scan gauge plugged into the OBD2 port is a way more accurate way of reading live temps. The idiot gauge is not that accurate.

You must be registered for see images attach

Here is more information that explains temps.
At halfway point your engine temp is between 178 degrees and 229 degrees.
At the 3/4 mark your engine temp is between 230 degrees and 259 degrees. At full hot (red zone) your engine temp is 260+ degrees.
The electric cooling fan (main cooling fan) turns on at 219 degrees(+/- a few degrees).
The mechanical fan (if you have HD cooling) "locks up" at 230 degrees if you have the stock clutch.


Confirm that both the low & high speed fan works.
Hoat coolant or Zerex G05 only to be used in the Kj's sytem. If wrong coolant was ever used it needs a complete flush.
Best way to remove all the coolant & replace, is by utizing a dealer's coolant re-circulating machine.
Pressure testing the system is the best way to know if there are any leaks or air entering system.
Mopar thermostat only should be used & has a built in gasket & air bleed pin.
Heavy duty cooling package with viscous fan helps a lot in summer.

 

[turblediesel]

The experts will be along soon.

I do know that there's a hole in the thermostat that needs to be oriented correctly. There's a bleed ***** somewhere high on the engine to get all the air out. Folks have some trouble getting all the air out of these engines. If regular green antifreeze gets mixed with the proper HOAT antifreeze it gels and clogs. Is your mechanical fan engaging properly?

*****
bolt
nut
wingnut
woodscrew

 

[DadOSix]

*****
bolt
nut
wingnut
woodscrew

Follow top radiator hose back to the block.

usually an 8mm head allen ***** there.

couldn’t get loose on 04 kj. 06 came out good and proper

 

[mduclow]

If it only overheats under heavy loads, my attention normally turns to the radiator.

I agree, radiator. I am looking at this: 3-row all aluminum radiator

... which is an all aluminum 3-row (1.73" thick core) radiator. It seems, by another listing with a review, that it is drop in with the only "complaint" being it needed an adapter for the trans lines and some trimming on the fan shroud.

I'm thinking I am going to buy this radiator if nobody has anything negative to say about it.

 

[mduclow]

I'll update this thread as I go along with this.

I purchased the 3-row all aluminum radiator, I expect it end of week or early next week. I intend to run the trans lines into it first and then send them along to the external cooler. This should ensure that the trans won't overheat with typical use. This combo should increase the amount of fluid in the system for both trans fluid and antifreeze increasing as a result the cooling efficiency of both.

Having been a muscle car builder I have dealt with cooling issues, so I feel pretty good with this 3-row radiator handling what I will ask of it.
I have used quite a few Griffin "big 2-core" aluminum radiators on small block and big block chevy's with excellent results, I'm hopeful this radiator will be similar in that regard.

I'm a big fan of "too much" brakes and "too much" cooling when upgrading, hopefully this fills that bill.

 

[Michael Noland]

I own a 2005 CRD. I was told by a friend who had a CRD that the computer needed to be reprogrammed because it showed hot when the engine wasn't hot. My dealer was clueless, so I've just ignored it. Check the temperature of the engine when it reads hot by using one of those infrared lazer thermometers sold at Harbor Freight. That's how my friend knew his engine wasn't overheating. I don't know if it applied to the 3.7 models.

 

[Michael Soberanes]

Hi everyone, I have an issue with a 2004 Liberty (3.7) running hot, I would like to see what the guys that know these Liberty's have to say about it. I grew up building cars, mostly GM/chevy's, but don't know the Liberty's like some of you do.

Here's the situation:
Since owning the Liberty it has a low threshhold for running hot.
Shortly after buying this Liberty with 187,000 miles in 2020 my wife and I put an aftermarket motor in it. A new water pump, thermostat and hoses were done with the motor as well. As to the thermostat, these were serious Jeep guys recommended to me, so I can only assume it is a proper t-stat and installed correctly. Other aspects of how it runs supports a good t-stat and correct installation (maybe).

I have verified that the electric fan is working as it should. When the A/C is turned on the fan does come on, even if it is cold and has just been started. I have confirmed (over a 45 minute period) that the fan does cycle between low speed and high speed. It appears to cycle properly.

So the car now has 200,000 miles, with a new motor (7,000 miles), new hoses, new water pump, and new thermostat with the electric fan verified to work properly.

When I drive it without the A/C it doesn't get hot, much. In hot summer temps climbing hills (with speed on the pavement roads) it might get a little hot (5/8's or less) but will cool down fairly quickly. If I take it into the mountains and start climbing it will quickly (within 10 minutes depending on outside temperatures) start running hotter, requiring a stop to let it cool down.

If I drive it with A/C (summer temps obviously) it will run hot, and quickly run hot with any strain on the motor, like climbing hills. It will be bad enough I need to turn the A/C off and then it will start to cool down within a couple minutes and cool down to halfway on the gauge in about 7 or 8 minutes if there is no strain on the motor.

I feel the vehicle is not properly dissipating heat through the cooling system. I don't think I have clogged passages through the motor (new), I think all but the radiator is confirmed working properly.

I am leaning (heavily) towards the radiator being original (200,000 miles and now 17 years), clogged and inefficient.

Would the experts in this area please chime in and offer your 2 cents worth?

Thank you!

My fan had a faulty connecter, discovered after replacing the thermostat. Now it runs great.

 

[XWrench3]

FWIW, I completely removed the thermostat from my Liberty (3.7L) after a complete cooling system flush including removing the radiator and flushing it. in normal temperatures (70-85) my Jeep runs between 165 and 180 degrees running down the highway (with the A/C running @ 85 outside temps. to me, that says the radiator is not actually completely clear (HIGHLY LIKELY since this had the wrong coolant when i purchased it) or if it is actually clear, its not big enough. i am certain that some form of hood louvers, or some other way of increasing the airflow out from under the hood would DEFINATELY help.

 

[OldJoe]

First, Verify that your temp really is high. Possible bad gauge. Secondly, that radiator, at 200K, has been around the block more than once, so changing it out wouldn't hurt and a new radiator from Rock is less than $100.

 

[OldJoe]

First, Verify that your temp really is high. Possible bad gauge. Secondly, that radiator, at 200K, has been around the block more than once, so changing it out wouldn't hurt and a new radiator from Rock is less than $100.

 

[mduclow]

I think I am going to put a good aftermarket water temp gauge in it also, maybe even one for trans temp

On the airflow issue, I've taken the gasket off the back rail where the hood closes, I'm going to shim the back of the hood a bit to open it up a little.
That will probably throw air at the wipers and have them all weird at highway speeds!

Living in Colorado Springs, I can go from 6400' at home to over 10,000' in less than an hour. I'm concerned wanting to run up those elevations in the summer with A/C is just plain too much to ask of the stock single core radiator. I am hoping the increase in surface area and coolant capacity with that all-aluminum 3-core radiator allows me a chance at doing just that. At $200, I think it's a great deal, many people pay way more than that to significantly increase their stock cooling capacity.

 

[Joe Lomorticello]

Hi everyone, I have an issue with a 2004 Liberty (3.7) running hot, I would like to see what the guys that know these Liberty's have to say about it. I grew up building cars, mostly GM/chevy's, but don't know the Liberty's like some of you do.

Here's the situation:
Since owning the Liberty it has a low threshhold for running hot.
Shortly after buying this Liberty with 187,000 miles in 2020 my wife and I put an aftermarket motor in it. A new water pump, thermostat and hoses were done with the motor as well. As to the thermostat, these were serious Jeep guys recommended to me, so I can only assume it is a proper t-stat and installed correctly. Other aspects of how it runs supports a good t-stat and correct installation (maybe).

I have verified that the electric fan is working as it should. When the A/C is turned on the fan does come on, even if it is cold and has just been started. I have confirmed (over a 45 minute period) that the fan does cycle between low speed and high speed. It appears to cycle properly.

So the car now has 200,000 miles, with a new motor (7,000 miles), new hoses, new water pump, and new thermostat with the electric fan verified to work properly.

When I drive it without the A/C it doesn't get hot, much. In hot summer temps climbing hills (with speed on the pavement roads) it might get a little hot (5/8's or less) but will cool down fairly quickly. If I take it into the mountains and start climbing it will quickly (within 10 minutes depending on outside temperatures) start running hotter, requiring a stop to let it cool down.

If I drive it with A/C (summer temps obviously) it will run hot, and quickly run hot with any strain on the motor, like climbing hills. It will be bad enough I need to turn the A/C off and then it will start to cool down within a couple minutes and cool down to halfway on the gauge in about 7 or 8 minutes if there is no strain on the motor.

I feel the vehicle is not properly dissipating heat through the cooling system. I don't think I have clogged passages through the motor (new), I think all but the radiator is confirmed working properly.

I am leaning (heavily) towards the radiator being original (200,000 miles and now 17 years), clogged and inefficient.

Would the experts in this area please chime in and offer your 2 cents worth?

Thank you!

Yeah I think the problem with your 02 Liberty is to check the male female connector at the fan it could have melted causing this over heating problem if that ‘s the case what you want to do is cut the male and female connector at the fan and hard wire it this is a common problem with the liberties good luck

 

[Carolyn Twiss]

Hi everyone, I have an issue with a 2004 Liberty (3.7) running hot, I would like to see what the guys that know these Liberty's have to say about it. I grew up building cars, mostly GM/chevy's, but don't know the Liberty's like some of you do.

Here's the situation:
Since owning the Liberty it has a low threshhold for running hot.
Shortly after buying this Liberty with 187,000 miles in 2020 my wife and I put an aftermarket motor in it. A new water pump, thermostat and hoses were done with the motor as well. As to the thermostat, these were serious Jeep guys recommended to me, so I can only assume it is a proper t-stat and installed correctly. Other aspects of how it runs supports a good t-stat and correct installation (maybe).

I have verified that the electric fan is working as it should. When the A/C is turned on the fan does come on, even if it is cold and has just been started. I have confirmed (over a 45 minute period) that the fan does cycle between low speed and high speed. It appears to cycle properly.

So the car now has 200,000 miles, with a new motor (7,000 miles), new hoses, new water pump, and new thermostat with the electric fan verified to work properly.

When I drive it without the A/C it doesn't get hot, much. In hot summer temps climbing hills (with speed on the pavement roads) it might get a little hot (5/8's or less) but will cool down fairly quickly. If I take it into the mountains and start climbing it will quickly (within 10 minutes depending on outside temperatures) start running hotter, requiring a stop to let it cool down.

If I drive it with A/C (summer temps obviously) it will run hot, and quickly run hot with any strain on the motor, like climbing hills. It will be bad enough I need to turn the A/C off and then it will start to cool down within a couple minutes and cool down to halfway on the gauge in about 7 or 8 minutes if there is no strain on the motor.

I feel the vehicle is not properly dissipating heat through the cooling system. I don't think I have clogged passages through the motor (new), I think all but the radiator is confirmed working properly.

I am leaning (heavily) towards the radiator being original (200,000 miles and now 17 years), clogged and inefficient.

Would the experts in this area please chime in and offer your 2 cents worth?

Thank you!

I have a 2002 Liberty and went through all the attempts that you did to resolve the overheating. As a last desperate attempt to FIND something; I revved the engine while someone looked under the hood. They found a flap on the radiator that looked like it was leaking a little water. Replaced the radiator. MAGIC! Has not overheated since!

 

[XWrench3]

> Additionally I lossened the purge valve, and it never stopped bubbling, even after an hour of letting it run, it never stopped bubbling. That is odd to me. "

that seems odd to me as well. the "oh no" might be a leaking head gasket. i know that there is a way to check if this is the problem by putting something in the coolant. but i do not know what it is. i have only heard tales of people using it.

 

[mduclow]

> Additionally I lossened the purge valve, and it never stopped bubbling, even after an hour of letting it run, it never stopped bubbling. That is odd to me. "

that seems odd to me as well. the "oh no" might be a leaking head gasket. i know that there is a way to check if this is the problem by putting something in the coolant. but i do not know what it is. i have only heard tales of people using it.

Let's hope that is not the problem (new motor), I don't see white smoke out the back which is usually an indication of that sort of thing

Still waiting on the new radiator. Removing the rear gasket across the back in the engine compartment sealing the back of the hood and shimming the back of the hood has helped some. It definitely is letting a little hot air out from under the hood.

 

[turblediesel]

The trick for checking for a blown headgasket is to start the cold engine and run it for a minute; shut it off and remove the radiator cap and see if it releases pressure. The idea is that the pressurization comes from compression or combustion gasses escaping the cylinder into the water jacket.

Head gaskets can fail other ways too. A simple water or oil leak can happen to atmosphere. Oil can get into the water or vice versa.