ARNESON ANODE

Function and technical context

Arneson Transmission Systems Sacrificial Anodes are cathodic protection elements specifically designed to defend the submerged metal parts of the attack surface unit against galvanic corrosion. This component works within the propulsion system, actively protecting the stainless steel, bronze and aluminum components of the Arneson-type driveshaft and tail unit, which would otherwise be exposed to electrolytic corrosion accelerated by contact with salt or brackish water. If the anode is completely consumed without being replaced in time, galvanic corrosion directly attacks the structural parts of the transmission, potentially compromising the integrity of the shaft, supports and watertight seals, with serious consequences for both the maneuverability and safety of the boat.

When to replace this part?

Sacrificial anodes should be inspected at least at the beginning and end of each navigation season, and replaced when they have lost approximately 50% of their mass, regardless of the time elapsed, since in waters with high electrical conductivity wear can be noticeably faster. Symptoms of a depleted or insufficient anode include pitting, whitish discoloration, or visible erosion on adjacent metal surfaces of the transmission, as well as on the seals and shaft. Replacing the anode preventively at the beginning of each season is the most economical measure to avoid major repairs to propulsion components, which can be extremely costly out of port.