To remove all of the air I took the top hose coming from the IC that drops into your cooler res. off. Then plugged that inlet with your thumb, put a rag over your res. opening and then blow into it. With the pump on its gonna push water through that hose thats off pretty fast, so just be aware. Seemed to work good and never had any problems since. If its not that then it could just be a worn pump. A new is 88 through Tousley Ford. Hope it helps.