Freshwater Anode Questions

[umblecumbuz]

Re: Freshwater Anode Questions

Electrolytic corrosion is not an exact science. That's why local knowledge is so useful. There is an Engine FAQ on the subject on this forum.<br /><br />Lakelivin said:

think I read that if I do this, the magnesium annode will sacrifice itself protecting not just my boat, but also the other annodes that are zinc. Could I be creating a bigger problem if I replace only one zinc annode with magnesium, even if it is the largest one?

The problem will be smaller, generally speaking, not bigger. The large mag anode will certainly sacrifice itself before the zinc anodes, but depending on the composition of the water, the zincs will continue to sacrifice at a slower rate, and this rate will speed up once the magnesium has gone.Replacing the magnesium is the best answer here - presuming it is needed in the first place. It's not common to use magnesium anodes.<br /><br />Bear in mind that the effectiveness of an anode does not depend exclusively on its composition. The surface area of the anode, and the cleanliness of its surface, also has a direct relationship to its effectiveness.