Hello and Merry Christmas everyone.

Well my 6.0 has started to lose a little coolant (half a liter <quart> a Month).
it is coming out the degas bottle and not the tailpipe. I know this because it is white with residue and every once and a while i will smell coolant. I have never had any smoke (other than Black) out the exhaust.
I am not a rookie on these engine's I work on than almost daily. So i have an good idea what goes on. I have auto enginuity with all the latest updates.
the truck is running in the stock setting for the last four months as it is winter here in Saskatchewan and icy roads don't need horsepower!
I have an SCT SF3 with Matt's tunes. the engine egr cooler has been welded shut for three years now, head gaskets were done at 80000 kms truck now has 230000 kms. oil cooler has never being replaced but i have changed the coolant on it three possible four times and have had a filter in the coolant for two years.
My thinking is that it is head-gasket issues again. but could it be something else? maybe plugged oil cooler? maybe my plug at the end of my egr cooler has burnt through? the truck runs like a champ, always has. the only time i have had problems is with the head-gaskets and that was covered under warranty.
I am looking for any ideas or similar problems anyone else has seen and their repair for it to try before ripping heads off and redoing.
Thank everyone

 

How old is your degas cap? It could be letting some "vapor" out before the system actually even gets close to 16 psi. I'd check that before dropping allot of money & time on something inside the engine.

 

hook a pressure gauge up to one of the hoses that ties into the vapor space of your degas bottle.

 

So if the pressure goes to around 16 PSI then the degas bottle cap is likely okay? If the pressure only goes to 10 or 12 (or less) then the cap is likely toast? Sorry for the newb questions. I am having the same issue as the OP and just not confident yet. Thanks.

 

Thats the way I look at it.

Ford states that whenever the cap relieves, it weakens.

Just be aware that if you have a cap that is relieving at 12 psig or less you could have two problems - the cap is weak AND something else is causing high pressures in the system. You will know this if the new cap also relieves - but at 16 psig.