VM ANODE PLUG

Function and technical context

The VM anode plug is a cathodic protection element that is installed at strategic points on the block or cylinder head of the outboard or inboard engine, acting as a sacrificial barrier against galvanic corrosion. It works within the engine's anti-corrosion protection system, exposing itself to the electrolytic action of salt, brackish or fresh water to preserve the metal surfaces of the propeller. Its function is to consume itself progressively instead of allowing the galvanic process to attack structural components of the engine such as the casing, block or cooling ducts. Without adequate cathodic protection, engine metals are exposed to accelerated corrosion that can render high-cost parts unusable in just a few sailing seasons.

When to replace this part?

The clearest indicator that the anode plug needs to be replaced is the loss of more than 50% of its mass due to erosion: when the zinc or alloy of the anode appears clearly reduced, pitted or crumbled, it has stopped offering effective protection. It is recommended to check all sacrificial anodes at the beginning and end of each navigation season, and replace them whenever they show more than half wear, regardless of the time elapsed, since in very active waters or in port areas with a high density of vessels, consumption can be very rapid. Changing the anode plug preventively at each annual maintenance is the most economical measure to avoid irreversible damage to the engine due to corrosion.

Compatibility table