Originally Posted by Jason4i7;13009513
This is incorrect. It is completely possible to have a 100% full loop. If it is not, then you are not bleeding it correctly. The only thing in your loop that should have air is your res. Technically, the res, while in your loop, is not part or your "flow" line. (Pump, rad, block) The res is the only thing that can or should have air. Even then it can still be filled to the top with minimal air. Air in the system can get trapped in many areas, the block, the rad. You just have to be patient and move the radiator around until it is empty of air. tilt, move, smack, w/e to get the air to move out of it.
if your using PTnuke, it should break up the surface tension of the bubbles to make them smaller so they can be filtered out of your loop and end up in your res.