Thanks for all your help. It seems that I was losing anti-freeze thru a valve that the previous owner had installed to bleed air out of the system. ( On the hose that ran into the heat exchanger) I would run the engine for 15 minutes and the antifreeze that I just put in would be gone. I just took the valve out put in something that would join the two hoses together and no loss of antifreeze now. I am going to see if i can get another valve since I guess its helpful to bleed air out of the system on occasion. Thanks, Richard