ANODE SHAFT 1''

Function and technical context

The shaft anode is a cathodic protection element specifically designed to be mounted on the boat's propulsion shaft, acting as a sacrificial material against galvanic corrosion. It works within the underwater propulsion system, protecting it from the electrochemical degradation that occurs when different metals coexist in a conductive medium such as salt water or fresh water with minerals. Being more electronegative than the surrounding metals—shaft, propeller, horn, and other driveline components—the anode corrodes in a controlled manner rather than allowing higher-cost structural parts to do so. Without adequate cathodic protection, the shaft can suffer pitting, loss of section and premature breakage that compromises the safety and maneuverability of the boat.

When to replace this part?

The clearest sign that the shaft anode needs to be replaced is visible mass loss: when the anode has lost approximately half its volume, it has completed its protection cycle and should be replaced without delay. As a general maintenance rule, the shaft anodes are checked and replaced at each annual or seasonal mooring, given that their useful life depends directly on the type of water, the navigation time and the intensity of the galvanic currents present at the mooring. Early replacement is the most economical measure to preserve the propulsion shaft, horn and propeller from damage that may require expensive workshop work.

Compatibility table