OMC Cobra Anode 395780 TEN00911

Function and Technical Context

The sacrificial anode for OMC Cobra engines (ref. 395780 / 0395780, replaced by 0433458) is a cathodic protection component located on the port side of the transom bracket, whose purpose is to concentrate upon itself the galvanic corrosion that would otherwise attack the structural metal parts of the engine and transmission. Manufactured from high-purity zinc alloy, this anode acts as the negative electrode in the galvanic couple that forms when the engine-vessel assembly is submerged in saltwater, brackish water, or even freshwater with high conductivity. Its correct installation on the transom bracket is essential to preserve the integrity of the marine aluminum of the powerplant group, preventing pitting, erosion and structural weakening of expensive components. Without cathodic protection in good condition, the housings, shafts and aluminum surfaces of compatible Johnson and Evinrude engines are exposed to accelerated and irreversible degradation.

When to Replace This Component?

The clearest indicator that the anode has reached the end of its service life is the reduction of its mass by more than 50%: when the zinc appears visibly worn, with a granular appearance or appreciable loss of volume, it must be replaced immediately before relaunching the vessel. As a preventive maintenance rule, it is recommended to inspect the anode at least once per season—or every time the boat is hauled out of the water—and replace it systematically at the beginning of each boating season, regardless of its visual appearance, if the vessel regularly operates in saltwater or brackish waters. Preventive anode replacement is the most economical protection measure against repairs costing several hundred euros due to galvanic corrosion in the engine group.

Compatible Johnson/Evinrude Engines

Equivalent Manufacturer References