I've never had a problem refilling the system. Fill it SLOWLY! I start with six quarts of anti-freeze, then continure with distilled water. When the level is at the full mark on the supply tank, start the engine and monitor the level (cap off). As the engine warms up increase revs to about 1500. Once the thermostat opens the level will drop, so add coolant to keep the level near the full mark.

When the thermostat begins of open, air will bleed out of the nipple at the top of the water outlet to the supply tank. Once the system will not take any more coolant, install the cap and take it for a short drive.

Monitor the supply tank level over the next few thermal cycles until it stabilizes and adjust as necessary.

The other task I do as part of a coolant change is clean the recovery tank. Disconnect the overflow hose at the fill neck and attach a length of service hose. Siphon out any coolant then siphon in about a pint of water and siphon it out to flush the tank. If the effluent is dirty reapeat the process until it is clean.

Duke