[Rinkerfam]

Merc. seems to have the most comprehensive anti-corrosion system of the stern drive manufacturers. They employ an active electronic anti-corrosion system called Mercathode. Newer Bravo III drives also feature an additional sacrificial anode on the anticavitation plate and on the prop-shaft. I am not sure what model year these additional anodes were introduced. Merc. also uses a multi-step paint system and ceramic coating to resist corrosion. My advice is: Make sure the anodes are zinc, inspect them for signs of deterioration (replace if necessary) and have the Mercathode checked to see if it is functioning properly. I'd be willing to bet that one of the most often overlooked maintenance items on a boat are the sacrificial anodes.