Sierra 18-6011 Zinc Anode for Mercury/Mariner Outboards 35 HP and Above and MerCruiser Except Bravo

The Sierra 18-6011 is a zinc sacrificial anode designed to protect Mercury, Mariner, and MerCruiser drive components from galvanic corrosion in the marine environment. Made of zinc, the anode is intended to corrode in place of surrounding metal parts, giving underwater hardware a longer service life. It carries a compact, machined design measuring 0.39 x 0.39 x 0.39 inches and weighs 1.11 pounds.

This anode fits most Mercury and Mariner outboards rated 35 HP and above, as well as all MerCruiser drives except Bravo. It cross-references directly to Mercury Marine part number 31640A1, Honda part number 41107-ZW1-003ZA, and OEM number 31640Q4, making it a straightforward replacement for the original anode on covered engines and drives. Like other Sierra parts, it is built to meet or exceed the specifications of the OEM part it replaces and is covered under Sierra's customer satisfaction warranty.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-6011
• Product Type: Zinc Anode
• Material: Zinc
• Exterior Finish: Machined
• Weight: 1.11 pounds
• Product Dimensions: 0.39 x 0.39 x 0.39 inches
• Fitment: Most Mercury/Mariner outboards 35 HP and above and all MerCruiser except Bravo
• OEM Cross-Reference: 31640Q4, Honda 41107-ZW1-003ZA, Mercury Marine 31640A1
• UPC: 030999320209

Fitment

• Most Mercury/Mariner outboards, 35 HP and above
• All MerCruiser drives except Bravo

Replaces (OEM)

• 31640Q4
• Honda 41107-ZW1-003ZA
• Mercury Marine 31640A1

Frequently Asked Questions

What engines and drives does the Sierra 18-6011 anode fit? The Sierra 18-6011 fits most Mercury and Mariner outboards rated 35 HP and above, along with all MerCruiser drives except Bravo.

Is the 18-6011 anode a genuine OEM part or an aftermarket replacement? It is a Sierra-manufactured replacement anode, not an OEM Mercury or Honda part, but it is built to meet or exceed the specifications of the OEM anode it replaces.

What OEM part numbers does the Sierra 18-6011 cross-reference? It cross-references Mercury Marine part number 31640A1, Honda part number 41107-ZW1-003ZA, and OEM number 31640Q4.

What material is the 18-6011 anode made from? The Sierra 18-6011 is made of zinc, which is the standard sacrificial metal used to protect submerged marine hardware from galvanic corrosion.

How big is the Sierra 18-6011 anode? It measures 0.39 x 0.39 x 0.39 inches and weighs 1.11 pounds.

Will this anode work on a MerCruiser Bravo drive? No, the Sierra 18-6011 is not for Bravo drives; it fits all MerCruiser drives except Bravo, so a Bravo-specific anode should be used instead.

Does the 18-6011 fit smaller outboards under 35 HP? No, this anode is designated for Mercury/Mariner outboards rated 35 HP and above; it is not intended for lower-horsepower models.

How do I know when this anode needs to be replaced? A zinc anode like the 18-6011 should be replaced once it has visibly corroded down to roughly half its original size, since its job is to sacrifice itself in place of surrounding metal parts.

Is installation of the 18-6011 anode something I can do myself? Replacing a Sierra 18-6011 anode is a straightforward hardware swap in the location of the original anode, typically requiring only basic hand tools.

Does the Sierra 18-6011 come with any warranty coverage? Yes, the 18-6011 is covered under Sierra's customer satisfaction warranty, as are all Sierra parts.

What finish does the 18-6011 anode have? The Sierra 18-6011 has a machined exterior finish.