2017 x15 Coolant system pressure test. Not losing pressure after 20 minutes ??

[BrandonOlsen]

(12-07-2022 )tree98 Wrote:  X15 doesn't use a crankcase filter, it's got some other new fangled system on it that cummins says never needs to be serviced

Your posts are quite confusing. Now you say your losing coolant when you pressure test, before you said it wasn't losing any pressure at all when you pressure test, which is it?

If your getting excess pressure in your cooling system it could be combustion gases from a dropped liner.
If you have established that your losing coolant and its not an external leak, the only thing left is either your burning it or its going into the oil. You could drop the dpf to see if your burning it.

To check for a dropped liner you'll need to pressure test it overnight with the oil pan off then slowly turn the engine by hand and look up at the bottom of the liners for drops of coolant, most likely #5 or #6.

My first initial pressure test was only 30 minutes long. Didn’t lose any pressure. Rawze suggested that I needed to pressurize it over night for several hours. So I had it pressurized all day and around the 8 hour mark is when it started to dribble out of the overflow . I’ll be pulling the dpf today and check that. I don’t think it’s going into the oil. I did have a oil sample done and showed no signs of water/coolant contamination.