ANODE SHAFT 3''

Function and technical context

Shaft anodes are sacrificial elements that form part of the vessel's cathodic protection system, acting directly on the tail shaft to prevent galvanic corrosion in marine environments. Being made of an alloy with greater electrochemical activity than the steel or bronze of the shaft, the anode preferentially oxidizes, protecting the metal of the shaft, the propeller and the bearings from surrounding water. Without adequate cathodic protection, galvanic corrosion can progressively degrade the propulsion shaft, cause pitting that compromises its structural integrity and ultimately generates serious damage to the transmission system. This 3-inch shaft anode (reference CMX-13) is installed directly on the drive shaft using clamping collars, ensuring continuous and effective electrical contact throughout the boating season.

When to replace this part?

The most obvious symptom of exhaustion of a shaft anode is the visible reduction in its mass: when the anode has lost approximately half of its volume, it has reached the limit of its useful life and must be replaced immediately. As a general rule, shaft anodes should be inspected at each docking or seasonal maintenance – at least once a year – and replaced whenever they show more than 50% wear, regardless of the time elapsed. Preventatively replacing the anode before each season is the best practice to ensure continued shaft protection and avoid costly corrosion repairs that can render the propulsion system unusable.