The system on the 6.0L is rated to 13 psi if im not mistaken. In a normal operating system with NO headgasket compromise and all other systems intact, is there any reason the system can or should exceed the 13psi rating and blow off coolant?


Thanks
Joe

 

The cap is 16psi.

Not sure I understand the question. Is there any normal reason why it should puke? I don't think so.

 

the cap is rated at 16 psi but i seriously have doubts that it actually comes close to that under normal operating conditions.

 

Sorry for the vague question....but bpounds that is basically what I was asking

daddykitty...Thanks for the clarification on the psi rating...


Joe

 

The cap can fail and not hold pressure. Lower pressure = lower boiling point.

If there is any doubt, a new cap is about $20 I think.

 

When my 6.0 started purging and puking out of the cap it had blown HG's. Just my 2 cents.

 

After I had my studs, oem head gaskets, oil cooler, egr delete, and everything else done, I installed a psi gauge off the hose on my degas bottle. With that being said after completly warmed up and a couple hard runs I've yet to see mine get over 8lbs. Also like was stated the cap is good for 16lbs. Also you should never puke, for any reason I can think of.

 

That is kinda what I was thinking....I was inquiring for a friend of mine who had his vehicle in for an inspection. the tech spliced off of the bypass hose to the degas bottle and claimed he "MAY" have a HG leak due to increased pressure while test driving said vehicle. The vehicle never pukes or runs hot....this is the premise for the question.

I told him to go get an insexpensive coolant sytem CO kit and check for sure. I don't buy the techs wanna be diagnosis.

 

Putting a gauge on the Degass Bottle tube to monitor pressure will tell him for sure. The question really is what was the "Increased Pressure"?

Additionally he should have gauges to monitor Engine Coolant (ECT) and Engine Oil (EOT) temperatures amoung other things.

Increased pressure can be caused by flash boiling (incorrect ratio of Coolant to Distilled water or perhaps incorrect type of coolant lowering the boiling point), and a compromised EGR cooler to name a few.

I currently have head gasket issues. The venting, over-pressurization, puking does not manifest itself visually unless I am towing and climbing a hill.

I can, and do, drive everyday back and forth to work with no venting. I need to add 0 coolant. Although I am certain that I have increased pressure in the degass bottle. I had TSB 09-08-03 performed to verify what I already new (Head gaskets) but I was concerned about the condition of my EGR cooler. It passed.

Over time the condition will get worse. I know of people who add a gallon of 50/50 coolant every morning thier venting is so bad. That is ridiculous in my opinion especially with the cost of the correct coolant.

To save your friend some money and pain, a Scanguage, or other reputable Guage package is essential to monitor critical parameters of this engine. It isn't a nice thing to have...It Is a NEED. The instrument cluster provides nothing useful except maybe RPM and MPH.

After getting the guage hooked up to the degass bottle I would get the truck out on the road, warmed up, and up to 65 MPH. Check the gauge PSI. The pressure in the system is designed to be less than 16 PSI. If he is pushing 16 or over it, there may be a good chance that indeed the head gaskets are compromised.

Eric

 

There are also some not all above board dealers out there. A lot are hurting for cash and look for people they think they can pull one over on. I let my wife take her jeep in for general maintenance just so I don't have to. She called because they told her the lower ball joint was so bad it wasn't safe to drive home. I had just replaced it a week before! They also wanted to do a full alignment when only the toe is adjustable and not affected by the lower control arm. I filed a fraud complaint and she doesn't go there anymore.

 

Typical pressure (generated by the liquid expanding as it heats up and compressing the vapor space) is 8-10 psig - give or take .............. depending on the beginning/cold coolant level and the hot temperature at which the coolant stabilizes.

 

There ya go....