You could have a leak in the damp area. Pressure test the system. If the leak is on the suction side of the cooling system, it'll draw in air, but not leak much coolant. Remember, a closed cooling system should lose no coolant.
With the leak sucking in air, you prol need to purge the air out of the system.

good luck

__________________
Closing the store
Benzbonz.biz on your smart phone or tablet.