Water Pump constantly loses Prime

[Scott Hamel]

John, I had a similar problem with our T/S car. You have a lot of air in the cooling system and once the pump gets loaded up with air no more circulation. I installed a petcock in the top of the water pump housing so I could bleed air out of it. Our radiator cap is in the upper hose and I found that if I ran the pump with the cap off it would actually pull air into the system there also. I never run the pump with the cap off now. I also bleed the system at the heads. Not sure if you could do that in your situation. You may have to bleed it a number of times to get all the air out. Always do your bleeding with the pump off. I would also pressure test the system to make sure you don't have a head gasket or head problem letting combustion pressure into the cooing system.