ANODE MAX PROP SHAFT 38.40 MM CMP83M

Function and technical context

Sacrificial anodes for propeller shafts are essential cathodic protection elements in any shaft-powered vessel. This Max Prop Anode for 38-40mm Shaft acts as a sacrificial metal by being galvanically more active than stainless steel or brass on the shaft, attracting electrolytic corrosion to itself and preserving the shaft, horn and driveline components. Proper installation in the submerged zone of the shaft is critical in salt or brackish water environments, where galvanic corrosion can degrade the propeller shaft in a single season if the anode is completely consumed without being replaced. The reference CMP83M is designed specifically for 38 and 40 mm diameter shafts, guaranteeing optimal fit and electrical contact for effective protection.

When to replace this part?

Shaft anodes should be inspected at least at the beginning and end of each sailing season, and replaced when they have lost approximately 50% of their mass, since below that level cathodic protection is insufficient. Symptoms of a depleted or missing anode include visible pitting on the propeller shaft, corrosion on the stern tube and damage to the sealing rings, signs that corrosion has progressed to more expensive parts. Replacing the anode preventively at the beginning of each season is the most economical maintenance measure to avoid replacing the shaft or propeller at the worst possible time.