I was swimming by my engine yesterday while it was tilted up and I noticed that something looked strange above the propeller. I went in a little closer and it looked like there was a piece missing so I opened up the parts catalog and it looks like #45 from the Gear Housing(Propeller Shaft) page is missing.
http://www.marineengine.com/parts/mercury_marine_parts/sn/0G963663/1031412WD/3021_270
It says that it's a zinc anode suitable for saltwater environments, but my boat is freshwater only so a quick google search tells me that I should get a magnesium anode. What is the correct part number for a magnesium replacement trim tab anode?
http://www.marineengine.com/parts/mercury_marine_parts/sn/0G963663/1031412WD/3021_270
It says that it's a zinc anode suitable for saltwater environments, but my boat is freshwater only so a quick google search tells me that I should get a magnesium anode. What is the correct part number for a magnesium replacement trim tab anode?