Sierra Zinc Anode 18-6115 for Johnson/Evinrude Stern Bracket, Replaces 433580, Fits 60-225 HP (1991-93)

The Sierra 18-6115 is a zinc sacrificial anode designed for mounting on the stern bracket of Johnson/Evinrude (OMC/BRP) outboards rated 60-225 HP (1991-93). As a sacrificial anode, it corrodes preferentially in place of the surrounding underwater metal components, protecting the stern bracket and adjacent hardware from galvanic corrosion caused by electrochemical reaction with the surrounding water and dissimilar metals.

This anode is built from zinc, which is the correct anode material for saltwater-only applications. Zinc anodes wear away over time as they perform their protective function, so periodic inspection and replacement is part of normal outboard maintenance in saltwater use. The Sierra 18-6115 is a direct replacement for OEM part number 433580, allowing straightforward like-for-like replacement on compatible stern brackets.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-6115
• Material: Zinc
• Application: Stern Bracket
• Recommended Water Type: Saltwater
• Fitment: Johnson/Evinrude (OMC/BRP) outboards, 60-225 HP (1991-93)
• Weight: 1.55 pounds
• UPC: 808282145132

Fitment

• Johnson/Evinrude (OMC/BRP) outboards, 60-225 HP, 1991-93, for use on Stern Bracket

Replaces (OEM)

• 433580

Frequently Asked Questions

What is the Sierra 18-6115 anode made of? It is a zinc anode. Zinc is the recommended anode material for saltwater-only applications.

What outboards does the 18-6115 anode fit? The Sierra 18-6115 fits Johnson/Evinrude (OMC/BRP) outboards rated 60-225 HP, model years 1991-93, on the stern bracket.

Where does this anode mount? The 18-6115 is designed for use on the stern bracket of the outboard.

What OEM part number does the Sierra 18-6115 replace? It replaces OEM part number 433580.

Can the 18-6115 zinc anode be used in freshwater? No. Zinc anodes are intended for saltwater-only applications; a magnesium anode is used for freshwater, and an aluminum anode is used for brackish or mixed fresh/salt environments.

How much does the Sierra 18-6115 anode weigh? The Sierra 18-6115 stern bracket anode weighs 1.55 pounds.

Why does an outboard need a stern bracket anode? A sacrificial anode like the 18-6115 corrodes in place of the surrounding metal, protecting the stern bracket and nearby components from galvanic corrosion in the water.

Is the Sierra 18-6115 a genuine Sierra part? Yes, 18-6115 is Sierra's own manufacturer part number for this stern bracket anode.

What is the difference between zinc, magnesium, and aluminum anodes? Zinc anodes, like the Sierra 18-6115, are for saltwater use only; magnesium anodes are for freshwater use only; aluminum anodes are used in brackish water or when a boat operates in both fresh and saltwater.

What years and horsepower range does the 18-6115 cover? The Sierra 18-6115 is specified for 60-225 HP Johnson/Evinrude outboards from 1991-93.