Ok, I found the filter strainer, and the seacock where it comes through the hull. It's under the rear berth floorboards on the port side of the boat. The hose between the seacock and the strainer has an outlet, looks like where a previous owner put a spot to blow the external strainer out without disconnecting anything. I opened that outlet, and water is flowing freely, so that's not it. Then I closed the seacock - visually I can see the water in the strainer (clear sides) and then I started the engine. I expected the engine to suck the remaining water out of the strainer body, but absolutely nothing happened. I then disconnected the intake hose from the engine side, and there was a random piece of rubber stick in the intake side of the pump body. Not *blocking* the intake per se, just kind of partially blocking it. I removed that piece of rubber, and blew out the intake hose from the engine side. Nothing came out of that but water. I reconnected the hose and tried again, but still no suction from the engine. I believe I may have a damaged / non-working pump / busted impeller. Thoughts?