ONAN ANODE

Function and technical context

This sacrificial anode works within the cathodic protection system of the Onan marine generator set, acting as an electrochemical barrier that protects the noble metal parts of the engine against galvanic corrosion produced by salt, brackish or river water. Being made of a metal with a lower electrochemical potential, the anode corrodes in a controlled manner before the block, the heat exchanger or the exhaust manifolds, which are expensive replacement components. Without effective cathodic protection, galvanic corrosion can quickly deteriorate the internal surfaces of the cooling circuit, causing leaks, loss of tightness and serious damage to the generator assembly. Its correct installation is especially critical on vessels anchored or moored with direct electrical current, where the risk of electrolytic corrosion is multiplied.

When to replace this part?

The clearest indicator that the anode needs to be replaced is the loss of more than 50% of its mass: when it appears visibly reduced, deformed or fragmented, it has lost its protective capacity and the metal parts of the engine are exposed. It is recommended to inspect the anode during each seasonal maintenance - at least once a year - and replace it preventively if it shows more than half wear, regardless of the number of hours of navigation. Renewing the anode at each annual tune-up is the most economical maintenance measure to avoid major repairs to the exchanger or generator block.

Compatibility