cooling pressure issue(video inside)

[bashbarnard]

So after trying a new rad cap for a while it seemed to work but the issues are now sadly persisting. I honestly have no idea whats happening. she is not losing water. not even a drop of it. but i still get this pressure that stays. Also the pipe in the video somehow always gets air. ive bled it up a few times. no overheating issues runs spot on temp wise for hundreds of miles on long trips with no issues at all. Is this pipe even needed?? how high up on the expansion tank do i fill. Also it has quite a strong mix of antifreeze in which i think expands more than water. 



maybe some waterless coolant? 



anyway here a link to the video please take a look as i have no idea and excuse the dirt this car is a daily and has stupid mileage put on it every week. 



https://www.youtube.com/watch?v=kD1Z4B0t...e=youtu.be

[Seb_Ryan]

If its always filling up with air, theres gotta be a leak somewhere.. Try a pressure tester on it? You know the pump up ones see if the pressure drops

[bashbarnard]

had a pressure test on it. As said no leaks. doesn't loose water and holds pressure itself. this is why im so confused.

[mr_fish]

Pressure tested when engine is hot/warm?

forgive me if you have, in worse case, possible crack in head expanding with heat?

[bashbarnard]

No i have not. Was about to update this. It appears to have fixed itself...
Only thing different is the coolant in the header tank i drained out a touch to allow it more room to expand. Seems to have worked. Went to it an hour ago at dinner no.pressure in there at all!!