Re: Hey don s..
If the drain on the water intake side of the raw water pump isn't closed completely, it will suck air, not water. Then you loose impellers and overheat engines. I truly HATE those fancy drain systems Merc has, they complicate things to no end, make it next to impossible to check to see if everything is drained properly or even check to see if they are actually closed when you try to run the engine again.
