Zinc Trim Tab Anode – Fits Yamaha 150HP 175HP 200HP 225HP Counter Rotation (Replaces 6K1-45371-02, 18-6121)

Product Details

This Zinc Trim Tab Anode is designed specifically for Yamaha outboard engines rated at 150 HP, 175 HP, 200 HP, and 225 HP with counter rotation configuration, covering model years from 1986 and up, including 4-stroke engines. This corrosion-protection component safeguards your lower unit by providing sacrificial zinc protection in saltwater and brackish environments.

This aftermarket anode directly replaces OEM part numbers 6K1-45371-02-00, 6K1-45371-01-00, and Sierra 18-6121, ensuring seamless compatibility with your existing mounting configuration.

• Sacrificial zinc material designed for saltwater use
• Direct bolt-on installation to trim tab location
• Compatible with both 2-stroke and 4-stroke Yamaha outboards in specified HP range

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket.

Engine & Model Compatibility

Confirm your engine model/year in the table below.

Technical Specs

Material

Zinc alloy

Configuration

Trim tab anode

Application

Saltwater & brackish water environments

Mounting Type

Bolt-on to trim tab position

Compatibility

Counter rotation engines only

What's in the Box

• 1x Zinc Trim Tab Anode

Installation Notes

1. Remove the old anode from the trim tab location using appropriate tools. Inspect mounting surface for corrosion or damage.
2. Clean the mounting surface thoroughly to ensure bare metal contact for proper electrical conductivity.
3. Position the new zinc anode onto the trim tab, aligning all mounting holes.
4. Install fasteners hand-tight first, then torque to manufacturer specifications in a cross-pattern.
5. Apply a thin layer of anti-seize compound to fastener threads if operating in saltwater conditions.
6. Inspect anode monthly and replace when eroded to 50% of original size or less.

Troubleshooting & FAQ

How do I know if this fits my counter rotation Yamaha?

Verify your engine is rated at 150, 175, 200, or 225 HP and manufactured from 1986 onward with counter rotation. Cross-check your current anode against part numbers 6K1-45371-02 or 6K1-45371-01. If your existing anode matches these numbers, this replacement will fit.

What's the difference between counter rotation and standard rotation?

Counter rotation engines spin in the opposite direction and use different lower unit components, including anodes. Installing the wrong anode may result in improper fit or inadequate corrosion protection. Always verify your engine's rotation type before ordering.

How often should I replace this anode?

Inspect monthly in saltwater use. Replace when the anode has eroded to 50% or less of its original size. Heavily used engines or those in warm saltwater may require replacement every 6–12 months.

Can I use this anode in freshwater?

Zinc anodes are formulated for saltwater and brackish environments. In freshwater, zinc can become passive and less effective. For freshwater applications, magnesium anodes are recommended. Consult your engine manual for guidance.

Why is my anode not corroding?

If the anode shows little erosion, check for paint or oxidation blocking metal-to-metal contact at the mounting surface. Ensure fasteners are tight and the anode has direct electrical continuity with the lower unit. Anodes also corrode slower in freshwater.

Will this work on both 2-stroke and 4-stroke Yamaha engines?

Yes, this anode fits both 2-stroke and 4-stroke Yamaha outboards in the 150–225 HP counter rotation range, provided they use the same lower unit design covered by the OEM part numbers listed.

Safety & Important Info

• Verify images/specifications against your original part. If anything differs—even if your model appears compatible—do not purchase.
• This is an aftermarket replacement, not an OEM component.
• Professional installation is recommended for safety and performance.