Sierra 18-6112 Magnesium Anode - Replaces 6J9-45371-01-00 - Fits Yamaha 150-200 HP Outboards

The Sierra 18-6112 is a magnesium sacrificial anode built to protect Yamaha 150-200 HP outboards from galvanic corrosion. Magnesium anodes are the correct choice for freshwater use, where their higher reactivity provides more effective protection than zinc, sacrificing itself first to keep the surrounding metal components of the outboard from corroding. Installing the correct anode material for your operating water is one of the simplest and most cost-effective ways to extend the service life of an outboard's underwater metal parts.

This anode is a direct fit for the OEM location it replaces, allowing straightforward swap-out during routine maintenance without modification. As a wear item, it should be inspected regularly and replaced once it has eroded to a fraction of its original size, since a depleted anode can no longer provide adequate cathodic protection.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-6112
• Material: Magnesium
• Weight: 0.47 pounds
• UPC: 808282103569
• Product Category: Yamaha Outboard Anode

Fitment

• Yamaha outboards, 150-200 HP

Replaces (OEM)

• 6J9-45371-01-00

Frequently Asked Questions

What does the Sierra 18-6112 anode fit? The Sierra 18-6112 magnesium anode is designed for Yamaha outboards in the 150-200 HP range.

Is the 18-6112 a direct replacement for OEM part 6J9-45371-01-00? Yes, the Sierra 18-6112 replaces OEM number 6J9-45371-01-00 and installs in the same location without modification.

What material is the 18-6112 anode made from? It is made from magnesium, which is the recommended anode material for outboards operated primarily in freshwater.

Should I use magnesium or zinc for my outboard? Magnesium anodes like the 18-6112 are intended for freshwater use because magnesium is more reactive and corrodes preferentially in low-salinity water; zinc anodes are the standard choice for saltwater use.

How much does the Sierra 18-6112 weigh? The Sierra 18-6112 magnesium anode weighs 0.47 pounds.

How do I know when to replace this anode? A sacrificial anode such as the 18-6112 should be replaced once it has corroded away to roughly a third or less of its original size, since it can no longer offer sufficient galvanic protection once significantly depleted.

Is the 18-6112 a genuine Sierra part or aftermarket? The 18-6112 is a genuine Sierra part identified by Sierra's own part number, manufactured specifically as a Yamaha outboard anode.

What is included when I order the 18-6112? Ordering the Sierra 18-6112 includes one magnesium sacrificial anode; mounting hardware fitment should be confirmed against the anode location it replaces on the outboard.

Why does anode material matter for corrosion protection? Anode material determines how effectively it sacrifices itself ahead of the outboard's metal components; using the wrong material, such as zinc in freshwater, can result in reduced protection because zinc does not corrode as readily in low-salinity water.

Does the 18-6112 have a UPC for ordering or inventory purposes? Yes, the Sierra 18-6112 magnesium anode carries UPC 808282103569.