VOLVO ANODE 200 875809

Function and technical context

Sacrificial anodes installed in the water passages of the cooling circuit act as electrochemical barriers that degrade in a controlled manner to protect the internal metal surfaces of the engine block, heat exchangers and pipes against galvanic corrosion caused by salt or brackish water. This 108 mm diameter anode is housed directly in the cooling passages of the engine, where the constant circulation of aggressive seawater would cause the noblest metals – aluminum, cast iron, brass – to suffer progressive electrochemical attack in the absence of cathodic protection. If this component is not present or is exhausted, corrosion advances silently on structural parts of the cooling system, potentially clogging ducts, deteriorating gaskets and compromising the integrity of the block, with the consequent risk of engine overheating and high-cost breakdowns.

When to replace this part?

The clearest symptom that a cooling anode is exhausted is the appearance of reddish or greenish deposits inside the water pipes, corrosion stains on the metal connections of the cooling circuit or, in advanced cases, a reduction in the coolant flow rate due to partial obstruction of the passages. It is recommended to inspect and replace the internal cooling anodes at the beginning of each nautical season or, at most, every 12 months of use in salt water; In areas with high electrical conductivity of water, the semiannual review is a common professional practice. Replacing this anode preventively before it is completely consumed is the most economical way to avoid repairs to the block or heat exchanger, interventions that can multiply the cost of this replacement tenfold.

Equivalent manufacturer part numbers