For the Greater Good
Corrosion is one of the biggest enemies of a boat and its machinery, and that’s why it’s important to have sufficient protection against it, that’s where sacrificial anodes are used… for the greater good.
Sacrificial anodes work by oxidizing more quickly than the metal it is protecting, being consumed completely before the other metal reacts with the electrolytes. Three metals that can be used are zinc, aluminum, and magnesium.
There are sacrificial anodes in various different parts of the boat, such as the hull, propeller and on your engine to protect your heat exchanger.
Over time the sacrificial anode will start to perish as a result of taking up all the corrosion that would have otherwise affected your boat, and thus they need to be changed at regular intervals. Pictured here is a sacrificial anode from the heat exchanger after its been well worn away, compared to a new one. We replaced this anode when we did our annual engine service.