Johnson-Evinrude Aluminum Anode CM327606A

Function and Technical Context

This aluminum sacrificial anode is part of the cathodic protection system of the outboard motor, acting as an active electrode that corrodes in a controlled manner to preserve the submerged metallic parts of the propulsion unit. When installed on the engine block or transom, it attracts the negative electrochemical potential and concentrates galvanic corrosion upon itself, protecting more costly components such as the shaft, propeller, and gearcase housing. Its proper function is especially critical in saltwater or brackish waters, where the conductivity of the medium accelerates oxidation processes and degradation of aluminum and zinc alloys in the motor. The reference CM327606A is compatible with OMC part number 327606, ensuring proper fit and performance on the Johnson and Evinrude models for which it is specified.

When to Replace This Part?

The most evident sign that the anode has reached the end of its service life is the visible reduction in its mass: when it has lost approximately half of its volume, it must be replaced immediately, as its protective capacity becomes compromised. Standard recommendation in marine maintenance is to inspect and replace anodes at least once per season, or more frequently if the vessel is moored in areas of high salinity or stray electrical currents. Replacing the anode preventively at the start of each season is the most economical measure to avoid galvanic corrosion damage to structural engine components that are costly to repair.

Compatible Johnson/Evinrude Motors

Equivalent Manufacturer References