I have a question about a '61 mercury 15 horse motor. There is a cover that contains the spring assembly for the transmission. On that cover is 4 screws total; 2 screws that hold it on, the grease vent, and a freshwater flush screw. What is the freshwater flush screw for? Is this something I should be doing as part of a maintanence schedule? Also, where the heck is the impeller for the water pump located? Any info would be appreciated.
<br /><br />The Flush screw is for running fresh water thru it if you ran it in saltwater or mud. There was an adapter that fit a garden hose. I used to have one, but don't recall ever using it. You could fit one together with a few plumbing fittings. The harder part would be at the motor end. The plug screw (3/8-16 thread) is bolt sized and you'd have to improvise a bolt with a hole bored in the center.