YANMAR ENGINE ANODE 27210-200370

Function and technical context

The sacrificial anode acts as a cathodic protection element within the engine's seawater cooling system, oxidizing in a controlled manner to preserve internal metal components – pipes, valve bodies, iron and steel blocks – from galvanic corrosion. Being made of a metal with a lower electrochemical potential, it attracts electrolytic degradation and concentrates it on itself, leaving the structural elements of the propellant intact. Without this operating component, circulating salt water accelerates corrosion of the internal surfaces of the block and the cooling galleries, compromising the tightness of the cooling circuit and drastically shortening the useful life of the engine. Its periodic replacement is, therefore, one of the preventive maintenance measures with the greatest impact on the durability of Yanmar marine engines.

When to replace this part?

Sacrificial anodes must be inspected at the beginning and end of each sailing season, and replaced when they have lost approximately 50% of their mass, since below that threshold they no longer offer effective cathodic protection. A clear symptom that the anode is exhausted or absent is the appearance of pits or corrosion deposits on the metal surfaces of the water circuit, as well as partial blockages in the cooling galleries that lead to increases in engine temperature. As a professional rule, it is recommended to replace the anode preventively at each annual seasonal inspection, especially in navigation areas with high salinity or parasitic electrical currents in the mooring, thus avoiding irreversible damage to much higher cost components.

Compatible Yanmar Engines

Equivalent manufacturer part numbers