Overheating need help

[MPieper]

Hello I have a 2005 Ram 3500 diesel. The truck has recently had a new radiator,waterpump electric fan and new hoses.
The truck still overheats espically after getting off the highway.
I did getbitbhotbtoday and noticed at about 210 degrees the ac stopped working and the electric fan no longer was running. I shut the truck off and restarted after 30 mins temp was about 180 and ac and fan were both running great. I am out of ideas of how to fix and a shop told me it may need an air-conditioner transducer, but only a Dodge dealer could confirm that?

Any advise would be great!

 

[AH64ID]

210° is within normal operating temps.

There is a reason these trucks still don’t have electric fans, they can’t move enough air. Why did you install an electric fan?

How are you controlling the fan?

The OEM 190° thermostat cracks at 190°, goes full open at 207°, and has a max allowable temp of 225°. Towing they will run 207-215° and that’s normal.

 

[MPieper]

Sorry is a new stock fan. It will get up to almost in the red and then start to boil over int the overflow. As mentioned the ac and cuts out and the fan will no longer run until it cools off. It never used to run this hot.

 

[AH64ID]

The red is 245°

What thermostat is in the truck? How old is it?

 

[Ozymandias]

What do you mean the fan stopped running - the hotter it is the more the fan has to run.
No way that things ever should stop in an overheat situation.

What parts were installed? All Mopar or Aftermarket? What codes are present?
What did you do with the truck that caused the overheat?

Thermostat installed upside down?

 

[Ozymandias]

Oh, and the temp gauge at the cluster is fake anyways.
It shows nicely around the middle range - until it really boils, then finally it virtually jumps into the red are.
Real water temp is only accessible through a scanner.

 

[MPieper]

What do you mean the fan stopped running - the hotter it is the more the fan has to run.
No way that things ever should stop in an overheat situation.

What parts were installed? All Mopar or Aftermarket? What codes are present?
What did you do with the truck that caused the overheat?

Thermostat installed upside down?

 

[MPieper]

Have not checked fault codes but will do. Thermostat is also brand new 195 I believe. That is the part that makes no sense why would the fan stop working when the temp goes up very counter intuitive to me. It also cuts out the ac compressor. Unless the only thing making the fan run is the ac?

I did pull a wiring diagram and it looks like the fan is controller by the ecu? Maybe that is crapping out when hot.

 

[AH64ID]

Have not checked fault codes but will do. Thermostat is also brand new 195 I believe. That is the part that makes no sense why would the fan stop working when the temp goes up very counter intuitive to me. It also cuts out the ac compressor. Unless the only thing making the fan run is the ac?

I did pull a wiring diagram and it looks like the fan is controller by the ecu? Maybe that is crapping out when hot.

The fan controller is the ECM.

Any programmer on the truck?

Are you sure it’s 195°? That’s not a Cummins temp. What brand thermostat did you use?

What about the radiator cap?

 

[brucejohnson]

May have something to do with something routed through the IPM (Integrated Power Module). Have to do a lot of bouncing around in the diagrams. May take a while to find a correlation.
Here is a part of the wiring diagrams for a 2005: Not quite complete though...still searching.
http://www.rambodybuilder.com/2005sbbgl/docs/wd/dr/wiringdiagrams/8w13integratedpowermodule.pdf

More 2005: Download and save this full wiring diagram.
truckmanualshub.com_Dodge Ram Truck 2005 1500,2500, 3500 Service Repair Manual - Wiring.pdf - Google Drive
8W-30-36 Cooling Fan

 

[MPieper]

The fan controller is the ECM.

Any programmer on the truck?

Are you sure it’s 195°? That’s not a Cummins temp. What brand thermostat did you use?

What about the radiator cap?

The fan controller is the ECM.

Any programmer on the truck?

Are you sure it’s 195°? That’s not a Cummins temp. What brand thermostat did you use?

What about the radiator cap?

Truck is stock about 286 k . Radiator cap is new thermostat was a carquest premium.

 

[AH64ID]

Truck is stock about 286 k . Radiator cap is new thermostat was a carquest premium.

Get a Genuine Cummins 190° thermostat and go from there. Lots more issues with aftermarket thermostats in these motors.

 

[MPieper]

Engine code is po118 coolant twmp too high.

 

[AH64ID]

Anything blocking airflow thru the radiator?

 

[MPieper]

Airflow is good power washed everything

 

[Darkbloodmon]

I did getbitbhotbtoday and noticed at about 210 degrees the ac stopped working and the electric fan no longer was running. I shut the truck off and restarted after 30 mins temp was about 180 and ac and fan were both running great.

Don't shut an engine off that's overheating unless the water pump has catastrophically failed. If you cut the engine the water pump no longer moves and the coolant flow stops. You aren't going to cool a heat soaked cast iron diesel engine anytime soon by letting it sit.

If the vehicle is getting hot turn the HVAC heat on inside the cab at full fan speed, if the vehicle is still getting hot pull over and pop the hood while HVAC heat is still on. Even better would be to pull over at a self serve car wash and spray down the radiator while the engine is running and while the interior heat is on full blast.

Truck is stock about 286 k . Radiator cap is new thermostat was a carquest premium.

The truck has recently had a new radiator,waterpump electric fan and new hoses.

Are you loosing coolant? When these components were replaced was the system properly bled? An air pocket can cause a temp spike/sharp fluctuation.

 

[brucejohnson]

Hello I have a 2005 Ram 3500 diesel. The truck has recently had a new radiator,waterpump electric fan and new hoses.
The truck still overheats espically after getting off the highway.

What were the original symptoms before the component changes were made?

 

[Ozymandias]

I'm pretty sure the thermostat isn't working, otherwise your head gasket gave way. Was this checked from the workshop?

I've driven mine for weeks with a broken Fan clutch, on flat land any speed was good, stop and go traffic was no problem. Only long hills needed some attention to the Temperatur.

And yeah, never shut down the engine in an overheat situation. Bad things happen then.

 

[Rowdy Dalton]

Don't shut an engine off that's overheating unless the water pump has catastrophically failed. If you cut the engine the water pump no longer moves and the coolant flow stops. You aren't going to cool a heat soaked cast iron diesel engine anytime soon by letting it sit.

If the vehicle is getting hot turn the HVAC heat on inside the cab at full fan speed, if the vehicle is still getting hot pull over and pop the hood while HVAC heat is still on. Even better would be to pull over at a self serve car wash and spray down the radiator while the engine is running and while the interior heat is on full blast.





Are you loosing coolant? When these components were replaced was the system properly bled? An air pocket can cause a temp spike/sharp fluctuation.

I had issues with an air pocket, after replacing my water pump, a while back. Now I always make sure to refill the coolant system from the thermostat hole first, then the radiator.

 

[bcbender]

Shouldn't have an issue with an air pocket on a 3rd gen 5.9 as the radiator is higher than the engine T-stat, I changed 2 water pumps and the radiator on my 04 and never touched the thermostat, just re-filled via the coolant tank, filled the recovery tank and went for a ride.. then level off the recovery tank and done.. It sounds like there is an issue as has been said with the T-stat, and / or there was a blockage of the bypass in the old T-stat.