Looked at a few more things today. Still Stumped. I did notice that the lower hose isn't as much cooler than the upper and more strange is that the overflow hose into the degas bottle has just a slight flow to it when sitting at idle fully hot, cap on and off the tank, but i didnt let it get fully back up to pressure to be honest. Shouldn't there be almost a slight vaccum from the pump?

It all started memorial day with it getting hot, but not overheating hitting a brutal hill with the trailer, did water pump and fan clutch cause it seemed fan clutch was weak even when fully hot spun fairly easy but you know how hard it is to tell. Could the radiator that went in a few months before somehow not be made correctly? Bad water pump or clutch that got replaced by a new bad one?

 

Well, took it in today. He tested, got it to lose coolant pressure and sniffer has it coming out the tail pipe. Quoted $3500 for head gaskets.

I guess I'll get it home and strip it down in the garage, question is head gaskets only or do the whole thing....

 

Whole thing? What year is your truck?

If your going to do head gaskets make sure to get the heads surfaced and jet washed by a competent machine shop.

 

Well bummer, didn't think that would be the problem with what you were describing and lack of coolant loss or pressurization of the coolant.
With the lack of coolant lost I wouldn't worry too much about damage to the lower end of the motor from coolant getting in the oil. How far you want to take it will depend on how many miles and the health of the motor...
You have really stumped me on this one, i've worked on many head gasket and cracked head problems on other engines and have never seen the exact problems you're experiencing?

 

Figured that was the issue seen it happen before on many cars slight head gasket damage from years of service, glad you taking on this job and saving some money

 

Well heads are off and at the machine shop. I ended up having a friends shop do it. Just time, stress and my back were worth it.

Bottom end looks perfect. Very little carbon, still crosshatched, no lip on bore, and definitely some work out gaskets along the way on intake and heads. A few exhaust studs broke off, but no leaks there.

Here is some pictures.

 

Well, head gaskets are done and ended up having the heads redone too. We're about 3/1000's out, one intake valve on each not seating completely. All back together and..... Not fixed. Back over there and awaiting word. I'm guessing we are looking at a short block too.

 

This is a good question that was never really answered.

The boiling point for 50-50 coolant mix is around 250° at 12 psi, if the head temps are hitting anywhere near 280° it should be pushing coolant out.

If it was actually burning coolant there is usually a greenish powdery colored coating on the cylinders and head that is leaking and i'm still a little confused how it could be leaking\burning coolant and the level not drop in the reservoir?

Does the dash temp gauge indicate it's overheating as well as whatever scanner you're using????

Just some of my thoughts while trying to figure this one out with the information I have.

 

Must have missed that. Been using torque to read the computer and verifying with IR guns.

Has not puked coolant out even at the worst. But there isn't a way to see the gasses 'boiling' it since the overflow comes into the degas bottle in the air chamber.

Yes dash guage goes stupid and it threw up warning lights when it hit 245/290 with the trailer. Testing with the trailer after head gaskets got me 244 on the coolant on flat freeway at 55mph when I turned around. Heads were about 270 already. I had not gone as far as before before turning around. Dash gauge did not go as high into the red but I don't really rely on it as its not that helpful clearly as the coolant was as hot but gauge didn't even get more than 1/4" above normal.

It does lose coolant from the reservoir but not at an alarming rate just topping it off is needed. It's never alarmed me because I've had the system open so much with work being done that it's hard to know when its truly burped it all out.

When I fired it up Monday to take it back to the shop my Dad witnessed smoke out of the tail pipe which a friend told me he had seen previously this year but didn't think it was anything.... It's never cold enough in Phoenix to be anything but an issue if its smoking on startup

 

That clears up a lot of questions and helps to keep us from guessing at random stuff.

At this point I am not inclined to think that any of the parts you replaced and many you rechecked are the culprit. I do believe the engine is getting hot but just not hot enough to boil the coolant completely. The only things I can think of at this point are.
-Did beheads get checked for cracks?
-does your torque scanner and read transmission temperatures? (totally out there guess but have heard of superhot transmission oil overheating and engine before)
-A blocked/restricted coolant passage in the engine block

And one more question, what color was the smoke at start up? White blue or gray? And how much and how long?

 

Well I feel like I am back to square one. Went out this AM to get the trailer hooked up for my test drive up a few hills on the interstate this afternoon and when I fired it up.... smoke out the tailpipe. A significant amount about half a second after it started. I was watching in the mirror so its hard to tell what color it was and I haven't heard from my dad on what he saw the other day but either way in my knowledge smoke from a tailpipe on startup is never a good thing. Its not like its condensation in the Phoenix summer here.

 

Dye test the coolant. And run a power balance test/compression check and post some numbers. Year and miles?

and how are you bleeding the system ? Airlift? or ezfill funnel?

 

Smoke looked to have a blue tint to me. Had my Dad watch and he gave me a color of blue too independently. I am going to heat it up good as it only seems to happen after fully heating it up then waiting a few hours. I will shoot a video.

As far as bleeding the system I don't think anything special was done?