I have a 1978 Mercury 500 that has a water issue. I replaced the whole water pump. The whole water pump. New upper and lower housing. All gaskets. New impeller. Checked and double checked my work but pump not working. I took off the lower unit and there is no evidence of water. I have the motor in a tank with water up to the top of the inlet screens. I'm thinking that I may not have the lower unit deep enough into the water column but before I open it up again I would like some opinions. The water pick up tube is correctly installed and seated in the pump. No water coming out of the pee hole.
