Zincs and boat anodes are the hidden protectors of our boats. Zincs are made in many different shapes and sizes in order to fit where electrolysis attacks the most. Shaft anodes, on the other hand, fit inside tanks and engine blocks in order to do the same thing.
What exactly are marine anodes?
In a nutshell, electrolysis is the effect of electrical current carried through the water and into and through the hull. Electrolysis will eat away at any and almost all metals in your boat. Boat zincs and anodes draw the electrolysis away from the metals and sacrifice themselves to the corrosion.
Rudder zincs, Shaft zincs - boat anodes come in many different sizes.
Shaft anodes usually are made up of two-piece that are fitted together around the shaft. These zincs are available in sizes to fit most propeller shafts. Rudder zincs are flat like a pancake and bolt onto the rudder and hull zincs are also flat and bolt to the hull.
Plug it in and forget it!
Well, that's not necessarily true. Plug it in and check it is better. Keep in mind that zincs should be changed when about 70% corroded. Check them often to get a feel for the corrosion rate, especially if you move marinas or even docks. Water heater anodes should be removed before winterizing and engine anodes can come out if you store your boat and engine.
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