In a message dated 11/8/99 5:19:46 PM Eastern Standard Time, Reggie_Knowlton@xxxx writes: << The cooling system will purge the air as it heats up, this is why you have an overflow cannister, the cooling system will expend the trapped air in the system as the engine heats up the trapped air will go into the cannister as the radiator cap opens due to the thermal element within and as the system cools it will draw needed coolant back into the system. This is called a closed cooling system. >> The cooling system should always be bled after system repairs, i.e., hose replacement etc. Bleed screw is located above water pump (see manual). Slip a clear plastic hose over the screw with the other end submerged in container of coolant. With engine running, open screw after thermostat has opened and purge until no more air exits, close screw. Burke