ANODE FOR YANMAR

Function and technical context

The sacrificial anode is the key component of the cathodic protection system of Yanmar marine engines: its function is to oxidize in a controlled manner to prevent electrolytic corrosion from attacking the most valuable metal parts of the engine, such as the outboard motor casing, tail components or heat exchangers. It acts as a negative electrode in the galvanic couple that is formed when different metals are submerged in salt or brackish water, attracting all the corrosive activity to itself. Without an anode in good condition, corrosion silently advances on structural parts of the propulsion group, which can lead to high-cost repairs or the engine being unusable during the navigation season.

When to replace this part?

The main symptom of an exhausted anode is its visible reduction in mass: when it has lost approximately half of its volume it must be replaced immediately, since below that threshold it stops offering effective protection. For Yanmar engines in regular use, it is recommended to inspect the anode at least once a season and replace it at the beginning of each sailing period or each time the boat is taken out dry for beaching. Replacing the TENPLAC-1 anode preventively is the most economical measure to protect the engine from galvanic corrosion and avoid serious breakdowns in critical parts of the propeller.

Equivalent manufacturer part numbers