I also noticed it was much easier to fill the radiator before burping the system. Remove the upper hose and start filling it up until it's full.

Once it's full, stick the hose back on the agua pump.

Then fill that resivor. It will slowly fillup the more you put into it.

I did that and went for a drive...I added ~1/2 after that intor the resivoir and it's been fine since.