Just recently I installed a new radiator into my '91 Legend... It was overheating for a moment and it wasn't activating the fans until the system was burped (bled the air out) completely. After all that... now it overheats after what appears that it's boiling off the coolant, cause I have to continue to refill after a week or so. Checked oil for blown head gasket, no leaks, and all other fluids are good... Can't understand whats the problem! Fellas can you help me?