Little back story. For about a year or so I have been having to top off my degas bottle with coolant. I eventually found out the coolant filter lines were leaking and that has been fixed. I've still had a drop in coolant level, but have been thinking that was maybe air in the system from changing the coolant filter lines. The same day I topped off the degas bottle, I towed a boat. When returning, I checked the coolant level and noticed I had puked coolant in the engine bay and its obviously coming from the degas bottle. Thinking I forgot to screw the cap back on tight, I added more coolant. I still noticed a loss of coolant, once again thinking air in the system from not having the cap tight. I towed the same boat this past weekend and once again, same result, puked coolant. I know my cap was tight and when unloading the boat to head home, my dad mentioned he could smell antifreeze; he's made this comment in the past. I have only experienced this gross amount of puke when towing. Boat is a 21ft fiberglass bay boat, total trip 120-150 miles for this past weekend and probably 30 miles for the first trip with boat.

Truck has 118k miles, EGR delete, I think I used the Riff raff diesel one, been over 12 years since doing the delete. Truck also been switched to CAT ELC red coolant. When doing the coolant switch, I followed directions on this site with flushing with a garden hose, flushing that with distilled water and then added so much straight coolant and then so much 50/50 coolant. I believe my mix is correct. When topping off the coolant, I have been using the same CAT Red ELC 50/50 mix. I have also been filling it at the min mark and I know when taking the boat out this past weekend, I was about a 1/4" below the min mark, so I don't think my issue is overfilling the degas bottle. I have also changed from the electrical fan clutch to the mechnical one.

After reading on here, I have purchased a new cap, from Ford, and ordered a pressure gauge to check my pressure at the degas bottle. Question I have, is there a preference to where I attach my pressure gauge? Hose in back of degas that runs side to side or the one more towards the front that runs front to back. Is there anything else I should be checking? I haven't pressurized the system to see if I am getting any other leaks either, as that is more time consuming than checking my pressure.

Thanks

 

If it's building enough pressure to puke out the degas bottle, I'd think any leaks would be noticeable.

 

One would think. I haven't looked to see. I think the puking degas is telling more than a leak esp being its only doing when towing.

 

You’re probably not gonna want to hear this, but a 6.0 puking coolant out the degas bottle when being worked is indicative of head gasket leaks. The caps vent at 15psi, and you won’t normally get to that pressure and beyond unless combustion gases are being forced into the coolant passages at the head. There are some other tests for this, but you are right on with getting a gauge and teeing that into the line at the degas bottle. Plenty of instructional videos for this on YouTube including Auto-medic and Diesel Tech Ron. You may want to also head over to the 6.0 section of the forum. You’ll find some good information on troubleshooting this issue. I don’t think it’s going to be good news for you to be honest.

Best of luck.

 

Check your thermostat and make sure it's not stuck closed. If it has the latest flash you won't know it's overheating unless you're watching the numbers from the OBD2 port or the engine blows up. The gauge won't move until it's too late.

 

Check coolant pressure with a gauge (range 0-30psi) with a "T" connected to hose degas bottle - radiator

 

Thanks. I was going to use a gauge, but when talking to my mechanic he told me to check the upper radiator hose after some accelerations and if it is hard, its probably a bad head gasket. I also couldn't find the fittings. I have gone today and gotten the fittings I need so I will check with the gauge. I checked my upper radiator hose and it was firm when up to operating temp and after some hard accelerations. I also allowed the truck to get up to operating temp, released the pressure and then drive around and I had pressure back in the degas bottle. Do you know what my pressures should be when I am checking with a gauge?

 

T-stat has water at a steady 193* on the interstate and when steadily driving. It drops when slowing down. Using scanguage for numbers

 

Truck currently does not have studs?

Test the coolant to see if it's contaminated by combustion, but it sounds like it's time for fresh head gaskets and some studs.