ANODE SHAFT 1-1/4''

Function and technical context

The shaft anodes are part of the boat's cathodic protection system, acting as a sacrificial element to protect the propulsion shaft against galvanic corrosion caused by prolonged immersion in salt or brackish water. This anode is installed directly on the tail shaft, being the component that absorbs electrochemical wear instead of the stainless steel or bronze of the shaft. Without adequate cathodic protection, the propulsion shaft can suffer pitting, thinning and structural weakening that compromise both the power transmission and the tightness of the stuffing box, which can lead to serious breakdowns and immobilization of the boat. This shaft anode is identified with the reference CMX-5 and is designed for 1-1/4 inch diameter shafts.

When to replace this part?

The clearest sign that the shaft anode needs to be replaced is when it has lost between 50% and 75% of its mass, indicating that it no longer offers sufficient protection; In no case should it be allowed to be completely consumed. Checking and replacing the shaft anodes is recommended at least once a season, coinciding with the annual docking of the boat, although in waters with high conductivity or with onboard electrical systems with current leaks it may be necessary to check them more frequently. Replacing the anode preventively at each grounding is the most economical measure to avoid corrosion of the propulsion shaft and the costly repairs or replacements that a damaged shaft entails.