I just purchased the Mercury Service Manual for my Bravo 3 drive. I was looking thru and I stumbled across the Mercathode information. I boat in fresh water and I get more than the average amount of corrosion on my drive. I am probably going to replace the electrode because I get the feeling that it has been painted by the PO of the boat. I also stumbled across an interesting statement, "In saltwater, a second MerCathode System blue controller may be added in parallel to increase protection to 400mA." I did the reference electrode test and I recall it being around 650mV in fresh water, which is low, and may be causing some of my corrosion issues. For the test, it gives you acceptable levels for fresh water and "Salt, Polluted, or Mineral Laden water". I have a feeling that the rivers that I boat in, The Allegheny, The Ohio and The Monongahela, are either mildly polluted or full of minerals. I do know that there is minerals in the water. I am wondering if I add a second MerCathode controller, would that give me the added protection that I need or would it be a waste of money.
2008 280 Express Cruiser, 6.2MPI, B3, Pittsburgh, PA