I just purchased a 2002 Maxum 2700 SCR with Mercruiser 6.2 and Bravo III outdrive. Prop is stainless steel. I'm seeing that my outdrive is taking quite a beating and the anodes are VERY chewed up.

Question : What can I do to stop and prevent this issue of electrolysis?

Replace your anodes and check to verify that the mercathode is still working.

See above:

Also, if it sits at a dock, you have some major homework to do, (google can help)
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'Also, a boat at the same dock hooked to the docks shore power can be eating your boat.

Oh, I'm sorry. You just bought it.

Yeh, so post #2 and read up on electrolysis and anode protection. . It's something all boat owners should have a basic understanding of.

stay away from stray electrical current that can take place at the docks of marinas. Also what others have posted.above ^^^^^.

Also the next bit of info is Bravo III see more issues because of the all the different extra metals that are built into the outdrive. The More dissimilar metals that are installed the faster corrosion / electrolysis issues .happens..

You can google dissimilar metal electrolysis and read about it.

We have our boat on a lift

This is what we have done - I'd appreciate some feedback.

When the boat is out of the water - and I mean all of it including the outdrive - which is stored in the down position I shut all the power off (battery switch) . Anytime the boat is in the water I leave the battery switch on - keeps the merc cathode working.

Make sense?

3pointstar

Does this make sense.

I have always understood that the Mercathode is / should be wired to be on at all times regardless of battery switch position.

I always thought that all the little ground straps that are on the gimble both inside and out were to help prevent this issue. Also make sure all the straps are intact and clear of corrosion at the contact points.

The straps keep conductivity to the anode and mercathode so the parts can be protected by them. Most corrosive material with good electrical contact will corrode first. More stainless and bronze, higher corrosion of the anodes.

Those 2 huge stainless props are the main problem. All B3's have corrosion issues if left in the water. Buy a bravo 1 lower and run aluminum prop if it is gonna live tied to the dock.