2005 CRD over heating

turbobill · **Posted:** Wed Apr 20, 2011 5:34 pm

I purchased a 2005 CRD limited in November last year. With the weather warming up in Texas I am having an overheating problem when I pull a long grade and the temperature is 85 or higher the temp gauge creeps up to about the 3/4 mark. I want to use the jeep to tow my bass boat but with temps headed higher this summer I am concerned it will really have an overheating problem.

I do have a bad thermostat, the jeep ran cool this past winter with temps below 60 or so. I am going to replace the T-stat but I am wondering if the defective T-stat could also contribute to the higher temperatures at higher ambient temps. The vehicle acts like there is a restriction in the cooling water system. I did check the T-stat by pulling the top radiator hose and it is not stuck. I have also changed the cooling fluid but it looked to be in great shape when I drained it so this appears to be an ongoing problem that the last owner did not discuss with me before I bought.

I love the jeep, and it does a great job towing my bass boat but I have to figure out this overheating problem before I can use it for towing.

Low speed or idle operation is not any problem, the Jeep will idle forever without heating up. All overheating occurs when pulling a grade at highway speed or towing a grade at 50 mph.

Any help would be appreciated.

Joe Romas · **Posted:** Wed Apr 20, 2011 6:54 pm

Replace your fan clutch. There were some bad ones on 05 models. There was also a flash for recalibrating the temperature guage so you didn't know it was getting warm :BANANA:

If your fan does not sound like a 747 taking off with a load of passangers the clutch is bad. It may sound like it's moving a lot of air but is not.

racertracer · **Posted:** Wed Apr 20, 2011 7:08 pm

Check to see if you have trapped air in the cooling system..... open the relief valve on top of the radiator when the engine is cold and see if any air comes out.

The valve is located on the passenger side of the radiator, it's made of plastic and it's flat, turn it from left to right 3/4 turn and listen for air escaping, it will stop when you see a small amount of coolant come out from around the perimeter of the valve opening.

And let us know what you find, you may have to perform this process a few times after driving the vehicle to get the system pressure up again and letting it cool down again.

How many miles on the vehicle, what color is the coolant, pink or green, does the coolant look clean in the plastic reservoir and when was the last time you did a coolant flush?

Is the system tight ... any leaks?

bhc04 · **Posted:** Wed Apr 20, 2011 7:18 pm

I have an 06 CRD Limited, owned since new. I live in Bullhead City Az. Is one of the hottest places in the U.S. in the summer. I run my Jeep all summer long in the past in temps as high as mid 120's few weeks in July/Aug. Never runs above center mark. Of course all fans running and also A.C. on high. Try getting a good flush and see if that fixes your problem. Cheapest way to go and can't hurt any.

ATXKJ · **Posted:** Wed Apr 20, 2011 7:46 pm

I'm in Austin - owned the CRD since new - the temp gauge has never been past 1/2 way while in Texas - only heats up climbing mountain passes in Colorado.
Before I go next time - I'm going to replace the fan clutch - and maybe the fan.
RetMil had a good writeup here
http://www.jeepkj.com/forum/showthread.php?t=46274

mdalien · **Joined:** Tue Jun 22, 2010 10:22 pm **Posts:** 41

My 05 has always had hot running issues. I had the thermostat and the fan clutch replaced last year.
I took off the electric fan after it got clogged with snow and fried.
It just doesn't seem to get enough air to the fan clutch to make it engage unless it is running real hot. :banghead:

My gauge was flashed once but still shows the overheat at the lower temp that unflashed units show.

I have sealed the gap between the radiator and the intercooler, I am going to see if I missed an area that is allowing the air to flow around instead of through the radiator.

turbobill · **Posted:** Sat Apr 23, 2011 3:26 pm

I have just completed a flush of the system. The fluid was a pinkish, orangy color, very clear. I flushed by filling with distilled water and running for a couple of days then draining and refilling. I did two cycles then filled with 50/50 Zerex G-05. Filled by lopeniong the vent on top of radiator and filling through the resevoir. I operated the engine with cap off for a while to make sure the engine/radiator filled. Cracked the vent and fluid came out so I thing I got all the trapped air out.

There was no change in over temp problem from old fluid, to Di Water to 50/50 Zerex mix. As I said in the original post I have a bad t-stat, the engine runs cold when the ambient temp is below 70 dg F.

My electric fan runs with the air conditioner and I have not had an over temp problem without the air conditioner running since it is always warm outside. With air on 1 or 2 the fan will not come on until the engine warms up (but it does come on), with it on 3 or 4 it runs all the time.

I have checked my mechanical fan when the engine is cold, it only rotates about 1 to 1 1/2 revolutions when pushed hard. When idling the fan rotates at a few hundred rpm (my guess). I have not blocked the radiator to try to heat up the engine so that the fan will hit high temp limit and kick on. When the Jeep is heating up I have not noticed a loud fan noise.

Is there an easy way to check the fan clutch high temp operations?

There is a sticker on the radiator that says a recall flash was completed (E37, I think). Was the temperature gauge recal included in that flash?

Thanks for your responses, I look forward to more info.

Joe Romas · **Posted:** Sat Apr 23, 2011 4:53 pm

No F37 didn't change the temperature guage. It was one of the ones for the Body control module (BCM)

A few years ago a user had 2 crd's a 05 and 06. He had a long steep uphill driveway, 1/4 mile as I recall, and his 05 overheated going up the drive but her 06 didn't. He replaced many parts before another member here lent him a hand. Between the two of them they figured it might be a good idea to sit the 05 and 06 next to each other. The 05 sounded ok by it's self but next to the 06 it was night and day difference.

So again if it does not sound like a loaded 747 taking off the clutch is bad. If you put your location in your info there might be a member close by willing to lend a hand :SOMBRERO:

papaindigo · **Posted:** Sat Apr 23, 2011 5:06 pm

Threads that may help: clogged radiator viewtopic.php?f=5&t=58582&p=651480&hilit=clogged+radiator#p651480; temp gauge misreading flash http://www.greendieselengineering.com/f ... t/19.page; fan issues including I think instructions on how to test fan clutch but if not search the forum or check the FSM viewtopic.php?f=5&t=50940; drain and fill procedure to purge air and get proper 50/50 G-05 mix viewtopic.php?f=5&t=60301

Other comments 1) the cooling system functions as if the radiator cap is located on the plastic reservoir on the firewall so treat that cap just like a normal radiator cap and fill the system from there; 2) often if you are really overheating you will constantly have to add fluid due to the excess heat causing excess pressure causing too much fluid to be pushed out the overflow; 3) if you can get access/loan of a infrared temp gun drive till you think you are over heating, pull over, while engine is still running check the temp reading at the tstat; 4) as noted in the drain and fill discussion we don't exactly know our system capacity and cannot drain all the fluid hence it's strongly recommended NOT to use 50/50 premix rather add the recommended amount of straight G-05, using permix won't cause an overheating problem but you may wind up with insufficient freeze protection and a tendancy to boil at a lower temp; and 5) our CRDs often run fine with no fan at all as far a temp goes, see a variety of forum chat some already linked.

warp2diesel · **Posted:** Sat Apr 23, 2011 5:14 pm

Joe Romas wrote:

No F37 didn't change the temperature guage. It was one of the ones for the Body control module (BCM)

A few years ago a user had 2 crd's a 05 and 06. He had a long steep uphill driveway, 1/4 mile as I recall, and his 05 overheated going up the drive but her 06 didn't. He replaced many parts before another member here lent him a hand. Between the two of them they figured it might be a good idea to sit the 05 and 06 next to each other. The 05 sounded ok by it's self but next to the 06 it was night and day difference.

So again if it does not sound like a loaded 747 taking off the clutch is bad. If you put your location in your info there might be a member close by willing to lend a hand :SOMBRERO:

If it is the fan clutch.

O'Reilly sells a Hayden Severe Duty Fan Clutch Part # 2905 that is built to much better specifications than Mopar stock. Hayden is built for the Hot Southern Summer Temps. If you want even more air flow, some of the older 3.7L ('02 & '03) fans with more blades will bolt up to the Hayden as well and move a lot more air when you need it.

Glend · **Posted:** Sat Apr 23, 2011 6:49 pm

I have the same heat build up problem when towing in rising terrain when the temperatures are above 34C (93.2F). The issue I believe is related to overfuelling (trying to maintain a descent speed under load on a grade) which can be detected by monitoring Exhaust gas temperatures (EGT). Once your EGT goes over 1000F (at outside air temps of 93F or above) you are making more heat than the engine can shed to the environment (whether via the cooling system or airflow) and the heat will slowly build (assuming overfueling continues) and eventually (if not reduced) the engine will be put into limp mode to protect it. Of course the use of AC does add to the heat load but it is unreasonable to think we should have to turn it off in those conditions to gain a small advantage.

I do not think that a fan clutch is the issue in your case because it would probably overheat without a towing load in rising terrain. I have tested my fan clutch and it works as it is supposed to.

I found, through the use of my gauges, that the optimal towing solution in hot weather is to hold the KJ in 4th gear with the TC locked up at about 1900 -2000 RPM, this has a couple of primary effects: first it changes the gearing thus you stop trying to hold overdrive 5th in rising terrain (which will mean overfuelling) by pushing ever more on the throttle, and it reduces transmission heat build up; secondly, EGT drops immeadiately to a more reasonable level like about 900F or less which means that less heat is being dealt with by the cooling system; thirdly, your fuel economy will be as good if not better than normal cruise on flat terrain (while towing) because your are in the rpm range where the VM engine is optimised for fuel economy (2000rpm). Have a look at this chart provided by VM:

Finally, IMHO all KJ CRDs should have a good aftermarket auxiliary transmission cooler to shed the heat generated there, and a transmission temperature gauge is a necessity. So in a nutshell, performance is optimised and temperatures controlled by managing the KJ operations to achieve the lowest possible temperatures on your: EGT, engine coolant temperature, and transmission (regardless of speed and terrain).

As a note, diesel Chips and Tunes modify fueling operations to produce additional power and this may mean that overfueling is used at some points compared to stock configuration (which can mean more heat being generated). Of course GDE's Tune does other things as well, like remap boost etc. I run the GDE Eco tune.

turbobill · **Posted:** Sat Apr 23, 2011 10:45 pm

Thanks to all for your assistance. It is supposed to be in the 90's tomorrow and I think I will check out my fan clutch by hooking up my boat and pulling it up hill for a while. i don't have a IR gun to check temp but I do have a meter that will measure temp, I'll try that to see if the temp gauge has been reflashed. If it has not been reflashed I think I would prefer that the gauge stay more sensitive, if I can compute a calibration cure for it.

I think I did try locking out OD but will try that as well with 2000rpm max during climb. I will post results.

Joe Romas · **Posted:** Sun Apr 24, 2011 9:31 am

I found the thread I was thinking of from 2008 :SOMBRERO:

You really need to find a local member with an 06 CRD :jester:

viewtopic.php?f=5&t=35341&hilit=driveway+fan+clutch+overheat&start=40

turbobill · **Posted:** Mon Apr 25, 2011 5:59 pm

Wools, lost my final update. Temp made it to 85 f so I hooked up my boat and tried to overheat my crd. I have a multimeter with thermocouple so I took it along to check engine temp. I got the temp gauge past the 3/4 mark, almost to red. Pulled over and t stat housing temp. It was 102 c so I have a wrong calibration on my temp gauge. I had a/c on 2. Electric fan was on high and mechanical fan clutch was not engaged but that should be normal operation for 102 c. It is supposed to be 98 tomorrows will strive to get to 234f to test fan clutch. Will call Chrysler dealer t chichi on getting a new cluster flash.

Thanks fr everyones help. Will make final update to this threAd when all is complete.

turbobill · **Posted:** Mon Apr 25, 2011 6:14 pm

Please excuse my typing and lack of editing on my last post. I used my wives iPad not a good idea

racertracer · **Posted:** Mon Apr 25, 2011 6:16 pm

Well good news and good work Turbobill.

Now when you do get that ECU software update, let us know how well your CRD runs, some have experienced a rebirth in our CRD.

Joe Romas · **Posted:** Mon Apr 25, 2011 6:25 pm

A conversion site I found says 102c is 215f and the standard operating temperature with a good thermostat is 176f so you are overheating to some extent.

You really need to contact another CRD owner who's jeep is not overheating and compare them. Your not the first and won't be the last to have this situation.

ATXKJ · **Posted:** Mon Apr 25, 2011 8:19 pm

I really like GDE's Thermostat drawing

6. Start the engine and operate at 2400 rpm. Within ten minutes the air temperature (indicated on the dial thermometer)
should be up to 93° C (200° F). Fan drive engagement should have started to occur at between 91°
to 96° C (195° to 205° F). Engagement is distinguishable by a definite increase in fan flow noise (roaring). The
timing light also will indicate an increase in the speed of the fan.
http://www.lostjeeps.com/forum/phpBB3/viewtopic.php?p=575149#p575149

if your fan wasn't on by 215F - it's bad.

JL Rockies · **Posted:** Tue Apr 26, 2011 12:21 pm

My CRD gets hot every summer since 2008. I've replaced the front fan, fan clutch and thermostat. I've also had the gauge calibrated, multiple flushes and have even tried the healing power of laughter. My solution: I bought a 4Runner!

Pastafari is going to be my last trip with this rig, I've already sold all of the aftermarket parts off of it, I'm putting it all back to stock and selling it to my dealership this summer. Driving around in the desert with the heat on really brings teh suk and I'm just tired of dealing with it. It's a great winter rig though.

racertracer · **Posted:** Tue Apr 26, 2011 12:37 pm

Is all the air out of it?

I am still getting small pockets of air out of mine, ever since when I replaced the thermostat a month ago. Just keeps getting smaller.

Keep turning the relief valve on top of the radiator.

2005 CRD over heating

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