03 6.0 Ex. Last towing season i never noticed this, but i have noticed lately that the fan seems to come on quite a bit. Was worried about oil cooler, so i scanned it and the delta was only 3-5 degrees. Buuuuuuuut... The coolant temp was running 210+ the entire time. Touched 228 degrees in town with the a/c on. These seems considerably higher than most other 6.0 trucks. This is all on flat ground... Unloaded.

Due to the tight delta... Im convinced the oil cooler isnt a problem. Where do i start? Thermostat maybe not opening all the way? Coolant is full and looks clean.

Thanks,
Zach

 

Change the thermo.

 

Moved to the 6.0L PSD forum where the experts can address your 6.0 specific question and get you fixed up lickity-split like.

Stewart

 

OK don't change it to start with.

 

I'm going to vote water pump impeller....

 

Did it seem to cool with higher engine speed? If so, then it's most likely a problem with the water pump (I think the early ones had some serious impeller problems that caused cavitation and impeller erosion??). If not, then I would try the tstat first, and if that doesn't help then the water pump.

 

On an 03 I agree the water pump is a likely culprit however the t-stat is much cheaper and easier to eliminate first and if it's the original probably due. They seem to usually stick open but then again??

 

Can't you rrmove the tstat (temporarily) and go for a drive and see what happens, for free? Drain some coolant into a clean bucket, remove t-stat put old coolant back in.

 

Thanks everybody for the input!
Grabbed a t-stat today, and got it put in. No change, other than the fact that I now have some really cut up arms! Driving around, the temps still got to 220*+.

Sounds as if those that suggested water pump may have been correct.

Here is a quick list of symptoms and info on how the truck is running:

On the highway - speeds around 70mph, A/C turned off - ECT went to 221*F. Would occasionally drop a bit to 217 (running down hill,) and went as high as 225*. EOT more or less mimicked the ECT fluctuations +~2-5*. Never saw a delta of more than 6*F between ECT and EOT. Coolant fan cycled often trying to get the temp back below 219*F.

ZERO coolant loss. Coolant stays full, and I have not needed to add any in the year and a half that I have owned the truck.

Is there anything else it could be besides the water pump? I am hesitant to throw a dealer a stack of cash to drop in another damn water pump that will fall apart again.

I'm considering taking the money I would save at the dealer, and doing the work myself with a bulletproofdiesel water pump, and at the same time, adding the sinister coolant filter (this has been on my list for quite some time.)

Just was looking for any other options/opinions on any other possible causes for this. Unfortunately for me, I am travelling next week out of state for work, then we are due to pull the camper 90 miles for memorial day weekend. Its do or die here - either I do it this weekend or I leave it at the dealer next week and get raped.

Thanks for any other suggestions/ideas/tips!

Zach

 

Bump for any last minute advice before I pull the trigger on this stuff.

 

Keep us updated.

 

If you're up to the work yourself, I would get one of the upgraded ones although I have no experience to suggest which one is best. Also, the coolant filter is a must, and this is the perfect time to do it.

If you're really looking to eliminate anything else, you could try doing a good thorough flush and reverse flush to make sure that the radiator isn't restricted, but then you risk more problems when there's a high likelihood of water pump problems.

 

Another cheap thing to check....Check for airflow blockage through radiator & coolers in front of motor. Could have bugs/leaves or whatever restricting airflow. If you have an air compressor, blow air through and between coolers/radiator. I prefer air, but a water hose would work as well. (not a pressure washer!) Just be careful not to bend any fins as you clean.

 

Update... I wanted to see if the pump was pushing water at all, so i pulled the heater hose before the vacuum actuated valve and started the truck. SOLID flow came out. I dont know what the spec is, but it was flowing VERY well. Went through about a gallon and it quit (i am presuming because it pulled all the fluid in the degass bottle.). Turned truck off, Filled the degass bottle back up, started the truck again to check for flow. Solid full flow once again of about a gallon or so.

Seems to me that water pump MIGHT NOT be the issue. Does anyone agree or disagree?

Again... Thermostat was replaced yesterday... No change.
Backyard water pump testing indicates that it is flowing a decent amount of water.


What the hell do I do now? Ugh.

 

Since you will be in so deep, how old are you radiator hoses?

You have an '03 - with origin radiator hoses?
you should consider replacing the radiator coolant hoses now, especially since they have been subject to so very high temps..