ANODE SHAFT 1-1/4

Function and technical context

The shaft anode is a sacrificial element that works within the boat's cathodic protection system, installing directly on the tail shaft to protect it from galvanic corrosion. Being made of an alloy with a higher negative electrochemical potential than stainless steel or shaft bronze, the anode preferentially corrodes rather than more valuable metal components. Without adequate cathodic protection, galvanic corrosion can attack the propulsion shaft, horns, intermediate supports and adjacent accessories, compromising the structural integrity of the assembly and the maneuverability of the vessel. The CMC-5 model is sized for 1-1/4-inch diameter shafts, fitting precisely over the shaft to ensure optimal electrical contact and effective protection throughout the boating season.

When to replace this part?

The clearest indicator that a shaft anode needs to be replaced is the visible mass loss: when the anode has consumed between 50% and 60% of its volume, its protective capacity decreases significantly and it must be replaced immediately. Inspection of the shaft anodes is recommended at least once a season, coinciding with the annual beaching, although in areas with highly conductive salt water or on vessels with poorly insulated electrical installations an intermediate inspection may be necessary. Replacing the CMC-5 anode preventively each season is the most economical measure to avoid degradation of the propulsion shaft and the costly repairs in the dock that come with a shaft damaged by galvanic corrosion.

Compatibility