If you are dumping that much heat into the cooling system I would still suspect there is exhaust heating it under a load.

Have you had a combustion leak test on it yet?

You can get one like this, I got mine from NAPA years ago, a real simple test you can do to rule out an exhaust gas leak.

http://blockchek.com/
make sure the test fluid will test diesel combustion gasses.

How is your water pump? I have seen the impeller fall off the shaft, I have gotten water pumps out of the box without an impeller.

Had anyone replaced the freeze plugs and left the old one inside the block?

How is the lower radiator hose? if the spring is broken it can collapse under high flow and starve the pump of coolant.

I had an engine with a lot of torque that was overheating, found out that the engine would torque in the frame and twist the lower hose shut.

Jim

 

In theory a cold engine that warms up without an increase in radiator flow normally indicates the thermostat is either stuck shut or installed backwards. If installed backwards the flow through the engine would then be bypassing the thermostat through the built in bypass design in the cylinder head and also possibly some through the heater core. This would provide an excellent amount of heat in the cab since it's also acting as the radiator. This built in bypass system is the reason for the specially designed two step thermostat. Normally you should see the flow increase as the temperature increases and the thermostat opens.

 

Pulled rad cap, thermostat, therm. housing, water pump, oil cooler, so far everything looks new and no answers.

Driving it this morning it would heat up and when I switched on the heater temp went down but would still rise under load.

If I switched the heater off it would climb up quickly.

I CAN'T WAIT to find out what this is!!!!!!!

 

So what sort of temps are you seeing on your aftermarket gauges, and where are they mounted? Do they drop when that fan clutch kicks? You said that it doesnt boil over when its hot, if it was my problem I would try running it without the tstat for a very short period (after a nice easy plugged in warm-up) to see how the temps differs...sounds like a major clog somewhere...good luck man

 

Is this with the thermostat removed or installed. NEW LOOKING does NOT indicate proper functioning. The normal thing to do is remove the thermostat and test the thermostat with hot water and a thermometer. If you can't do that then remove the thermostat and retest how it functions without the thermostat installed. If it functions normally then replace the thermostat. You are saying the thermostat was installed in the proper direction of the flow having the larger protruding end toward the block?

Also, when you replaced the head gasket did you do an overlay match between the old one and the new one?

 

I'm doing the test after one more coffee.
If it is pooched it was a dud from the get go, it's only a couple of months old.
I had a had a mechanic help me with the HG so no worries there.
Engine is not boiling over but I have never felt an upper rad hose with so much pressure as I did yesterday. Still moved the coolant back towards the thermostat when I squeezed it.
I'm going to start undoing heater lines today and force air through them and see if I get coolant coming out the other end of the circuit.
By lunch I'll have the whole system gutted so I should know by then.

 

I'm chasing an over heating problem and learned a bunch about our system from this thread.

What did you finally discover was your problem?

 

I ended up going to a commercial radiator shop and the following were my problems.

Rad crap was brand new but garbage. I had about a dozen pin holes in my intercooler (I made my own pressure tester for about $9.00) and my new rad had taken a rock off the road and were the rock was stuck you could barely see it once the rad was removed but it was causing the intermittent leaking and the coolant smell. And my fan clutch would work when it felt like it. It was always tight when it was cold but when it warmed up it stopped working. (I'm not a fan of grabbing a spinning fan but did it with the old one and could hold it at temperature with my finger and thumb)

So....I bought a new cap and had the radiator fixed (a 4 core rad I had had made up a couple of years ago) put in a different intercooler, (this one leaks as well but not as bad and I'm putting in a Gen 2 cooler this weekend) and was fortunate to grab some parts off my old neighbor a couple of miles down the range road. I picked up a like new rad shroud, and the piece of material that rests on top the rad and the front clip. I replaced the clutch with a "Four seasons Part #36936 standard rotation, severe duty thermal fan clutch" from Rockauto.com

Truck now holds temps under control and I feel the problem is now fixed!!

I have now learned all new parts aren't "new" and don't work out of the box sometimes.

Hope this helps and good luck.

 

Makes it more hard to diagnos when its multiple problems huh.

 

Now I'm having over heating issues. Have another thread about it.. why am I over heating... how do you check and make sure the coolant is flowing and check the water pump to make sure it's working?

 

how does that fan clutch work? dodge discontinued theirs, and i bought one that doesnt work at all. ive had it at 220 and it still wont kick on. my truck has been overheating as well, and ive been trying to find a fan clutch that works like it should.

 

Go with the Rock Auto one I listed previously. It is a SOLID component.

Just finished with a aluminum PS intercooler upgrade with the Cooler Tubz and got into my pump and put the Power Pin back in and the 3200RPM spring.

OOOOOOOOOOHHHHHHHHHHH BABY!!!!!!!!!!

That was what I was looking for all this time for power and torque. Mileage is still excellent as well.

This old girl can pull with full tongue weight all day long with the long pedal mashed to the floor!!!!!!!

The big irony to this whole story ends with a different twist.

While I was having the cooling issues my wife wanted to do a spur of the moment camping trip with the 5th wheel. I told her the truck wasn't quite ready and she got more than a bit upset with all the work and the breakdowns I have been having.

In the end she bought me a 2012 Chev Siverado LTZ Z71 4x4 crewcab with the 6.6

Pretty hard to say no to a brand new truck but she is done with the Dodge side of the house.

The clinch is my Dodge is now running PERFECT so I'm in truck heaven!!!!!!

I still do nothing but smile while I drive my old girl and it gets more miles put on it than the new one.

Just sold my '72 FJ40 last night so I'm thinking it's time for more upgrades!!!!! Back to the stickies to plan!!!!!!

 

Geez, she must REALLY be mad at you...