ISUZU KB360 Auto D/C 4x4 engine overheating.
Get connected: comment, discuss, share your experiences and air your opinions on Drive Out’s 4x4 off-road and African overland travel-enthusiasts’ forum.

Feel free to add your voice to this forum by clicking on your topic of interest and submitting your comment.

Alternatively, if you wish to add a new thread simply “Sign in” with your username and password at the bottom of the page. Then click on the category that your new thread will be related to and add your new topic.

Posted on behalf of Martin Esslinger

I have an ISUZU KB360 Auto D/C 4x4.
The engine overheats so often, the warning light for the auto transmission
temperature comes on and the auto box does not change into 4th gear anymore.

GM/ISUZU is adamant that the ARB bulbar is to blame.
According to them, they have already removed two bullbars from like models
experiencing the same problems.
They also say that the ARB Bullbar is not approved by GMSA.

I removed the Bull bar and the engine did not overheat anymore.
I re-fitted the bullbar, without the spotlights and the temperature rose again,
up to the 3/4 mark.

The ARB representative from Cymot could only comment that the radiator fan is to small.

Any comments or solutions would be apprecaited


Regards
Martin Esslinger

Replies

Hi Martin,Unfortunately the

Submitted by KaravaanMeester on Mon, 04/19/2010 - 14:13.

Hi Martin,
Unfortunately the ARB bar is the aftermarket equipment thus the supplier can not state that the fan is too small. If the vehicle does not overheat with the bar  removed the problem is clearly with the bar and it restricts airflow.
Make sure that the Radiator fins is not clogged up with mud and gras etc and the only way to do this is to remove the radiator, this is often the cause.
If not, my suggestion would be either to modify the ARB bar  to increase airflow or else speak to Robert  at dune offroad, robert@duneoffroad.co.za and have a look at the Dune Bar for the D-teq


Hope you get this sorted.


Regards
Johan Terblanche
(Isuzu Offroad Club)

Hi Martin,I must agree with

Submitted by KaravaanMeester on Mon, 04/19/2010 - 14:43.

Hi Martin,
I must agree with what Johan is saying. It makes sense. From what you are saying, GM agree also, and it seems to have been proven simply by removing the aftermarket bumper.
I have attached a couple of pics for comparison. Take a look at the ARB bumper and compare it to the pic of our bumper, taking note of the area below the grill adjacent to the number plate. We have ensured that there is as much airflow as possible to the radiator, to cater for areas where the temperatues are higher, by adding air vents in that section of the bumper. You will notice the ARB bumper is completely closed in that area. We have not had any problems to date with temperature on our customer's vehicles after fitment of the replacement bumper.
I agree with Johan that it would be in your best interest to modify the bumper in that section to allow improved airflow to the radiator below the grill.
 
Best Regards
Robert Hale
www.duneoffroad.co.za
"Raising your standards"

IMAGE 1:

IMAGE 2:


 

Posted on behalf of Martin

Submitted by Nadine Thomson on Mon, 04/19/2010 - 14:54.

Posted on behalf of Martin Esslinger:

Thanks for your responses and suggestions. Appreciated!
 
Johan, the radiator etc is clean. This is definitely not the cause.

Robert, thanks for the suggestion. I will take the modification up with Bernd.
 
What bothers me is, that to date I have not heard from anyone who has the ARB fitted to the 360KB Auto and does not have have this problem. Why?

I also can not believe that ARB would sell a product that was not properly tested and would cause the engine to overheat.
 
What bothers me the most though is that there is no pattern to the overheating. It happens during city- , off-road- , long-distance-driving at various speeds and driving styles, or not at all !

And I had the ARB fitted for over 8 months before the overheating problem came up. I have also noticed that the fan sometimes keeps on running for some time - up to 5 minutes - after hard/long driving and sometimes not at all.
I have asked ISUZU to replace the temperature sensor controlling the electrical fan. We are now waiting for this part to arrive.
My suspicion is that the fan sometimes kicks in too late or runs at a too low speed.
The ISUZU has an electric fan which (apparently) has 4 speeds.

Since I have this overheating issue I have noticed that the fuel consumption has increased drastically. It is now always around 20L/100km or 5km/L - irrespective of driving conditions and style.
Could these two issues be interlinked?
 
Any comments are appreciated.
Regards

Martin

Hi Martin I have had some

Submitted by Visitor on Wed, 04/21/2010 - 20:40.

Hi Martin


I have had some heating issues with my Isuzu KB LX 3.0 D D/C Auto D-Teq.


Usually the problem occurs when  towing my Afrispoor offroad trailer up a long incline on a hot day.  I have learned to control the problem by locking down to second gear.  Shortly after I ascend the crest of the hill the temperature returns to normal.


On a recent trip to the Berg from Durban the problem occured driving up the long hill past the Pavillion.  I took the ramp to Pinetown and pulled into Key. The technician from Key went on a test run with me.  The vehicle did not resume the symptoms.  One thing I did notice when the vehicle overheated was a significant loss of power.    The Key technicians opinion was that the computer chip is programmed to cut power when overheating.


On ascending Sani Pass last August I was driving behind some irritatingly slow vehicles over very rocky road surface.  Ths time the gearbox overheated.  I pulled over to let her cool down.  Wjen I resumed it happened again.  After this I locked down to 2 in low range.  No further gearbox heating for the rest of the day even though I went all the way up Black Mountain.  Since then I have ascended Sani with no gear heating problems.  I have obtained a copy of a GM memo to dealers advising them of a gearbox heating issue when the vehicle is ascending a steep incline.  Their advice was lock in second.  I have followed this advice and have found it works


My Isuzu is fitted with a winch on a custom made bracket.  Perhaps the winch sitting in front of an air intake just below the grille does not help the situation?  I am certainly convinced that the iIsuzu's electric fan provides insufficient cooling in certain conditions.


Question is, is it possible to fit an override switch and manually select the fastest fan speed when the vehicle is under load?

Hi Martin. In response to

Submitted by KaravaanMeester on Wed, 04/28/2010 - 09:30.

Hi Martin.

In response to your queries, please see my answers below,

Regards
Johan

What bothers me is, that to date I have not heard from anyone who has the ARB fitted to the 360KB Auto and does not have this problem. Why?
Are you saying that everyone with an ARB has got this problem ?

I also can not believe that ARB would sell a product that was not properly tested and would cause the engine to overheat. Please understand that I am not saying that the ARB was not properly tested. I base my replies on the info given to me not on anyone's reputation.
You info stated that the vehicle overheats with the ARB fitted and with it removed it does not, this clearly points to the fact that the ARB restricts airflow more that the standard bumper does. whether this is within spec or not  is to be investigated.

My suspicion is that the fan sometimes kicks in too late or runs at a too low speed.  My original question was whether your cooling system is 100% sound. If the fan is not working to spec currently then it might be that without the ARB there is just enough airflow over the radiator to hide the problem.
Thus it might be that the ARB bar does not allow the same amount of airflow over the radiator as what the standard bumper does, if this is the case it means that for eight months the fan had to work harder than under normal conditions to get the same amount of airflow and might have lead to premature fan failure, but this is all based on assumptions as we don't yet know 100% that the fan or the sensor is  faulty.

Maybe see if you can devise a  plan to deflect more air to the radiator especially from below the ARB bumper. just as a troubleshooting mechanism. Very difficult to sit here to try and solve this on email :)
Good luck with this and please don't hesitate if I can help any further.


Posted on behalf of Martin

Submitted by Nadine Thomson on Wed, 04/28/2010 - 09:54.

Posted on behalf of Martin Esslinger

Thanks Johan,

1.  According to GM all KB360''s they have seen with ARB bullbars have this problem. I have not heard of anybody who does NOT have this problem. Nor has ARB confirmed this.

2. Only ARB can answer this. I have send my original to ARB via their website but did not get ant response from ARB directly.

3. According to GM everything is OK. They will fit a new temp sensor next week and I will ask them to check the fan to confirm that it is still 100% OK.
I have cut 2 additional holes into the bumper today. By tomorrow I should know what the effect is.

Regards
 
Martin Esslinger

Just an update: I cut two

Submitted by Nadine Thomson on Thu, 05/06/2010 - 14:40.

Just an update: I cut two holes into the ARB to improve the airflow to the radiator. The engine temperature was still going above the halfway mark but did not go up to the 3/4 mark anymore. Ambient temperature is now also lower, so the holes may have helped.
ISUZU fitted a new temperature sensor and now the the temp gauge hardly goes above the halfway mark ! The radiator fan now also runs more often at the higher speed. Again, ambient is now lower than in summer, but I get the feeling the switch caused the overheating. 
I will be doing a dune trip in July, lets see what happens...
Regards
Martin Esslinger

Unfortunately the problem

Submitted by Nadine Thomson on Fri, 05/21/2010 - 10:33.

Unfortunately the problem still persists.
We did a trip to the Okavango Panhandle and were fully packed for a week long camping trip.
Up to a speed of 120 the temperature held, but driving at 140 the temperature rose to halfway between the 1/2 and 3/4 mark. The same happened when driving through thick sand in 4x4 H at an average speed of 30km/h. The outside temperature was around 30°C.  While driving at night with an ambient below 20°C the motor temperature did not go past the 1/2 mark.
This means that neither the additional openings in the ARB nor the new temperature sensor did the trick.
Seems that GMSA is correct then that the ARB is the cause?
I will ask GM to remove the ARB and replace it with the standard bumper and nudge bar. Does anybody want a used ARB bull bar?
Regards Martin

Hi MartinA petrol motor works

Submitted by Nadine Thomson on Fri, 05/21/2010 - 10:50.

Hi Martin
A petrol motor works very hard in the conditions described above. Which corresponds to the driving conditions mentioned in the Owner manual.
This is the owner manual for the Dmax.
According to the Owner manual. Page 2-2
"Stop - start driving in heavy traffic, driving at high speed in warm weather, hill climbing or towing may cause the needle to move toward the extreme top of the gauge. This is normal, and is no cause for concern. However, if the needle movesall the way to the H mark and remains there for more than 30 seconds, you should stop the vehicle as soon as it is safe to do so."
Regards Johan

Thanks for the hint Johan, I

Submitted by Nadine Thomson on Fri, 05/21/2010 - 10:51.

Thanks for the hint Johan, I will take this up with the ISUZU dealer. It seems then that after the modification to the ARB the engine operates within these limits as per the owners manual.
My concern still is that at high speed - 160 the engine eventually does reduce power because of the overheating - and this on the open road with one passenger and no luggage. It does take up to 2 hours driving at this speed before this happens. Surely today's vehicles must be able to handle this?
Based on all this I now tend to agree that the cooling system is not sufficient for our summer temperatures under severe driving conditions.
Regards Martin

Reply to this topic

All rights reserved. © Drive Out 2009. Published in South Africa by Media24
Digital Media and Marketing Association