ANODO HELICE RIVA EJE Ø 20-30 (AL)

Function and technical context

The propeller anode for Ø 20-30 mm aluminum shaft acts as sacrificial galvanic protection, interposing its metallic mass between the propeller shaft and the marine environment to absorb electrochemical corrosion that would otherwise attack the shaft, the propeller and the submerged metal elements of the propulsion system. It works on the boat's underwater transmission system, specifically mounted on the tail shaft through a mechanical adjustment appropriate to the diameter range of 20 to 30 mm covered by this RIVA reference. Its function is critical because, in the absence of sufficient anodic protection, galvanic corrosion can degrade the stainless steel shaft, the bronze surfaces of the propeller and even attack the watertight seals of the stern tube, generating vibrations, looseness and, in advanced cases, rendering the propulsion assembly unusable. The aluminum composition makes it especially suitable for salty and brackish waters, offering adequate protection effectiveness without overcorrosion in environments of regular use.

When to replace this part?

The clearest sign that the anode needs to be replaced is a reduction in volume of more than 50% compared to when it was new, indicating that it has consumed most of its sacrificial mass and no longer offers sufficient protection; Other symptoms associated with poor anodic protection are the appearance of pitting or surface erosion on the shaft or propeller, as well as whitish or reddish deposits on adjacent metals. It is recommended that the shaft anode be inspected and replaced at each seasonal docking, at least once a year, or sooner if the boat is moored in areas with high electrical conductivity of water or high eddy currents. Performing the preventive change at each annual tune-up is the most economical measure to avoid the costly replacement of a shaft or propeller damaged by galvanic corrosion.

Compatibility table