help with coolant issue
 

Just replaced all 3 radiators, used a pressure tester (no leaks) and a vacuum tool to refill. Was able to add exactly the same amount in as came out. When the car is warmed up it stays steady at 180 for an hour so no overheating issues, but the coolant tank level drops a bit until i remove the cap and relieve the pressure it goes back to where it was. see vid

When i got home the bleeder valve was up, but no air was coming out (bad bleeder valve?)

thoughts?

Not sure if its relevant, but I had a tiny leak in the bleeder cap(not the filler cap) so I replaced the two O-rings(large & small), cleaned it up and that solved my coolant level issues. I too had replaced all radiators and used the vacuum refill tool. I did go one step further and bought the $25 bottle of Porsche coolant "assembly lube". Best investment ever.......used it on all hose O-rings, etc.......parts glide together and no leaks. Used the lube on the bleeder O-rings as well.

Give it 3 to 5 full heat/drive cycles to let the fluid level stabilize. After i replaced my water pump that is what it took until it stabilized and the fluid level was steady. it been 2 years now and i have not had to touch it.

+1
It is not a "Bleeder" it is a vacuum break. Run the engine through a few heat cycles. IE: Drive around until thoroughly hot. Then let it cool with the bail up. That breaks vacuum to allow air to migrate to the tank and get pushed out through the vent in the cap.
Next time you go for a ride leave the bail down, stop after the car is up to temp and look at the shaft the bail is on. Up without the bail holding it? How does that happen??

you didn't bleed it properly is all ( my guess ). see above ^.

you need to run the car, valve UP.. for a bit. then close it, and top off ( or not ) as needed. i usually have OVERflow puking until i close the valve on the cap.

FWIW, I use old Sparkletts 5-gal water bottles to measure the coolant drained from the car, then I use some more to add the same volume back with the vacuum filler tool. Done this a few times, never had to manually raise the "valve", a few drive cycles and the level is steady. Yes, I keep about 5 empty bottles in my garage, also used to transport used coolant to the local recycle facility.

could have a small air pocket even with vacuum bleeders i have had issues because of how much coolant piping there is.

Get some heat cycles of driving the car and recheck.

when you used the vacuum tool to refill did you pull a vacuum to a minimum of -30 hg? if not theres the issue. may still have some air in the system or a hose/line not fully tightened