MERCURY TAIL ANODE 826134Q

Function and technical context

The tail anode is a passive cathodic protection component installed in the aft area of the outboard motor, specifically in the cooling and transmission system. Its function is to sacrifice itself electrochemically to prevent the base metal of the motor (aluminum alloys and stainless steel) from galvanic corrosion when the motor is submerged in salt or brackish water. Acting as the preferred negative electrode, the anode protects critical engine parts (body, tail gears, cooling passages) from marine corrosion degradation. Without this component, corrosion would progressively advance, compromising the tightness, power transmission and functionality of the cooling system.

When to replace this part?

The tail anode must be replaced when it shows visible erosion, loss of material or has reduced its size by more than 50%, clear signs that its protective capacity is compromised. It is recommended that the anode be inspected and replaced at least once per boating season, especially in frequent saltwater boating, and replaced preventatively if the engine has been idle in saltwater for weeks. Replacing the anode preventatively is a minimal financial investment that prevents costly gearbox repairs, cylinder head corrosion or damage to the cooling system that can render the engine unusable.

Compatible Mercury Mariner Engines

Equivalent manufacturer part numbers