: Screwed up water pump



bschelle
05-18-04, 03:04 PM
Well I just scewed up!! I installed a new NAPA water pump in my 99 DeVille and it still leaks. When I was installing the pump, it rotated like the stops were broken off. I mean that it didn't stop at any one posistion, it just rotated in the housing. What did I do? Did I break something on the pump or on the pump housing? The old pump was leaking down on the frame on the pulley side and the new pump is spraying up towards the hood on the hose side of the pump. I need expert advice so I can fix the car and get my wife off my back!

BeelzeBob
05-18-04, 03:27 PM
I would remove the pump cartridge and inspect the locking tangs. The machined details in the water pump casting locate and lock the tabs on the water pump cover. The steel cover of the water pump has the locking tangs in it that lock into place and should stop the pump in the locking detent when you turn it.


You turned it counterclockwise to install it, correct. It is a "left handed" install.

There is a o-ring between the cover and the casting that seals the face of the water pump to the crossover casting. IF you look into the cavity when the old pump cartridge is out you can see the o-ring in the groove. Was the o-ring replaced...???..It should have been. If not, that could cause a leak out the opening in the crossover casting where the pulley sticks thru. Make sure and lube the o-ring with some straight anti-freeze/glycol when installing the pump so that it slides against the o-ring.

From your description you are seeing a leak between the pump cover and the water pump casting....the 4 bolt cover that was removed to access the water pump itself. Remove the cover and inspect the cover and seal. There is a perimeter seal that seals the cover to the water crossover casting. Possibly it is out of position. If the seal is cut or something, you can clean the surfaces up carefully and spot repair with a dab of orange silicon seal (RTV) and reassemble. Keep the joint with the RTV dry until the RTV sets up...i.e...do not refill the system for 24 hours. You must allow the RTV to cure before the system is filled or it will not work correctly and will leak later (not allowing the RTV to cure before "using" the joint is why RTV gets a bad rep.....)

bschelle
06-04-04, 02:57 PM
I found the problem! I bought a pressure tester and pumped it up and the lower hose had a pin hole in it! Glad I bought the tester.