1996 mercruiser 7.4 sea water pump wont pump
 

i had it rebuilt because the fuel pump thats mounted on it froze up so i rebuilt the pump i put a new fuel pump and new bearing and seals in the raw water pump housing and the impeller and plastic housing was fine but now it wont draw water frome the outdrive any help would be appericated

99.9% chance you have the water lines backwards, even if you think you dont, I bet you do...Dont ask me how I am so sure of this...:lolhit:

I say the same thing,,,,Ive only done it almost every time Ive changed the impellor also...

Have a friend with the same problem 1995 7.4, hoses are correct.

Are you on the garden hose or in the water?

Hose with 2 people. Was working fine on hose before adding 2oz of oil to low press fuel pump on top of impeller.

CHeck the seals around the impeller housing. There are 2 "O" ring that needs to be replaced. One goes on the "Pump". The smalller one, the other around the stainless steel plate. if there is leaks or lack of seal, you may not get enough or any water. It's suction so it may be sucking air instead of water. if you'r on the hose, the hose preassure may get you the water, but once you no longer providing external force the impeller just sucking air.

MHO.

Have a low water intake on a Bravo 1 with the correct flush kit - didnt work so took off the pipe and put the hose straight onto the water pump it was fine.

Do you think I might have a leaky pump - o rings all changed?