Coolant Loss

[Sunday]

Yesterday I had to add a little over a gallon of coolant to my overflow bottle. My temps on my CTS read normal and my delta was 6-8* difference. Long story short my truck is not overheating, my delta is ok and I'm losing coolant. Anybody have a clue where I'm losing it at? Thanks in advance.

[seanhoffman]

i have the same issue, but mine has escalated....ive been told that its my EGR cooler gone bad....I have a current thread started just to verify what ive been told......Your pushing it through your exhaust and dont even know it!

I was also told that a delete kit will fix it.....in my thread i ask about that too...follow the responses on my thread and maybe we'll both get our answer

Sean

[seanhoffman]

did you see the reply i got....i think we have the same problem

[xpbprox]

it could still be your egr, usually you can smell it in the exhaust.

[devster55]

I am having the same problem. I was told to replace oil cooler and put a delete kit on it. I'm going to go the extra step and put a coolant filter to help prevent this problem in the future

Sent from my PG86100 using AutoGuide.com App

[HAM_RADIO_MAN]

Originally Posted by seanhoffman

did you see the reply i got....i think we have the same problem

Here is the post you got An EGR cooler can fail without the oil cooler being bad. They are made out of very thin stainless steel ( 409, I think ) Stainless steel will work harden from the thermal cycling the occurs in the normal operation of an EGR cooler. Over time this work hardened metal gets brittle and cracks. I see it on steam jacketed cooking kettles all the time.




Yes, It's time for a delete or weld that cooler up. Heres a link to my job. Make sure you clean the turbo when you have it out, Or else you will be pulling it out again to clean it. I removed my EGR cooler and welded it shut. Good Luck

No longer a 6.0 virgin. New STC, Cleaned turbo, welded EGR cooler closed. PIC's



READ THIS ENTIRE POST, LOTS OF GREAT TECH INFO FOR A NEW 6.0 OWNER:

No start issue? Look here.


Q: Engine puking coolant from de-gass tank

A: Head gaskets are bad or EGR cooler and oil cooler have failed. There is a slim chance the de-gas tank cap is bad.


Q: Wrench light when towing and engine looses power

A: Some newer PCM flashes monitor EOT vs ECT delta and when it exceeds 15 deg the truck will go into limp mode. Your oil cooler is obstructed and needs to be replaced. This is a good time to do a cooling system flush and an EGR delete. This can also be caused by a t-stat that is stuck open and not allowing the coolant to warm up.


Q: Do I have a blown EGR cooler?

A: Remove the EGR valve and look down the hole, some times the truck will have to be parked nose down over night. If you see any wetness, wet gooey soot, or it looks steam cleaned, your EGR cooler is bad. This is a good time to do a delete if you can, if you can't I would recommend a new cooler from bullet proof diesel.


Q: Do I have a blown head gasket?

A: Generally if there is a slow gradual pressure increases in the cooling system over 16 PSI then this points to an EGR cooler / oil cooler failure. If the pressure in the cooling system tries to head to and exceed 20psi pretty fast in a cool motor then this points to a head gasket failure. Put a Tee in one of the rubber lines going to the de-gas tank and attach the line for your gauge to that. Or buy new hose and make a test rig to use for now and then loan to all your buds later on. This is as simple as a 3/8 hose barb Tee,5 clamps, 30 PSI gauge and some 3/8 air line. Cut 2 short stubs out of the air line to span the gap between the manifold and the de-gas tank. Next since you saved the end of the air line that has a 1/4 FNPT fitting crimped to it, the free end goes to the tee and your gauge attaches to the factory crimped on FNPT fitting. You will use a gauge with a 30 full scale reading. The cap on the De-gas tank is a 16 lb relief, this is why 16 psi is the magic number. The pressure you reach is not as important as the rate of climb. The reason for the slow increase in pressure for the EGR cooler/ oil cooler failure is as follows. The oil cooler plugs up and starves the EGR cooler for coolant thus turning it into a superheated steam generator. This point source of heat and excess pressure will lead to the EGR cooler failure. In this condition some have reported the melting nipple on the de-gas tank the attaches to a rubber hose that vents steam from the EGR cooler.

The rapid rise in pressure associated with a head gasket failure is caused by combustion gasses entering the cooling system and raising the cooling system pressure until the vent on the de-gas tank cap opens and the puking starts. I think NAPA has a test strip you can use to detect combustion gasses in the coolant.

OK so with a quick check of a saturated steam chart this is what we know.

15.3 PSIg steam equals 250 degF

20 PSIg steam equals 259 degF

What this mean is that if you take a cold truck out and run the heck out of it and it builds pressure to 20PSI or more and the coolant isn’t 260 deg then it’s a safe bet that combustion gasses are entering the cooling system because you have a bad head gasket.

Water boils at 212 deg at zero PSIg. In a closed system there is a very predictable relationship between steam pressure and steam temperature. This is why cooling systems are pressurised. This way you can have 248 deg coolant that is at about 15 PSIa and you make no steam because the coolant isn’t it’s boiling temp for that pressure, it is however saturated. Now at addition of ethylene glycol raised the boiling point too but for what we are taking about we can use a table for water-based steam. If the system doesn’t get hot enough to the point it should make steam and its building pressure you know that pressure is from a different source like combustion gasses entering the cooling system. From ---- wait for it ------ BAD HEAD GASKETS.

Q: What is the delta between EOT and ECT?

A: Delta refers to the difference between the oil and coolant temperatures. This delta should not exceed 15 deg F , if it does once the truck it up to operating temperature going straight down the highway your oil cooler is plugged up.