ANODO LAPIZ Ø17mm (ZN)

Function and technical context

The 17mm diameter zinc pencil anode acts as an electrochemical sacrifice to protect the submerged metal parts of the outboard or inboard motor from galvanic corrosion. Being made of zinc, this anode preferentially corrodes before the noble parts of the engine - such as the block, the shaft or the heat exchanger -, diverting towards itself the flow of electrons that generates the potential difference between different metals in contact with water. Its pencil format (small diameter cylindrical) allows it to be installed in internal locations of the cooling circuit or in dedicated plugs of the engine block, where the plate or fin anodes do not have physical access. Without active and correctly sized cathodic protection, galvanic corrosion can silently destroy critical components that require high replacement costs.

When to replace this part?

The most obvious symptom that the pencil anode has reached its useful life is the visible reduction in its mass: when the anode has lost approximately 50% of its volume it must be replaced immediately, since below that threshold it no longer offers sufficient protection. The preventive review and replacement of the pencil-type zinc anodes must be carried out at least once per nautical season or every time the boat remains stranded for a prolonged period; In waters with high conductivity or ports with dispersed currents, wear can be noticeably faster and require intermediate checks. Replacing the anode on time is the lowest-cost maintenance intervention that exists in a marine engine, and omitting it can lead to irreversible corrosion of the block or exchanger, with repairs that multiply the price of this component by a hundred.

Compatibility