I just replaced some parts in my lower unit and am putting it back on. On top of the water pump there is a plastic tube where the water comes out. It slides over a metal tube that runs up to the engine. This plastic tube is very loose on the metal tube, so lose that water can bypass and not 100% of the water from the pump will ever make it to the engine. I didn't see anything when I took it apart but is there supposed to be some type of bushing or seal to make that a tight fit or is some water supposed to bypass?