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Yamaha Outboard Magnesium Anode Kit – Fits Yamaha 200-250 HP (Replaces 6G5-45251-01M, 61A-45371-00M)

Regular price $29.78

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U.S. orders usually arrive within 6–15 days, depending on stock location and destination.


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Product Details

This Yamaha Outboard Magnesium Anode Kit is engineered to provide superior corrosion protection for Yamaha 200-250 HP outboard motors operating in fresh water. The kit contains essential bracket and skeg anodes designed specifically for use in lakes and rivers.

It serves as a direct replacement for Martyr CMY200250KITM, Seachoice 95241, Sierra 18-6132, and Tecnoseal 21104MG.

  • Application: Fresh water only (not for salt or brackish water).
  • Installation: Simple bolt-on process with included stainless steel hardware.
  • Material: High-purity magnesium alloy meeting US Military specifications for maximum protection.

Part Number Matrix

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

Brand Part Number
Yamaha 6G5-45251-01M
Yamaha 61A-45371-00M
Martyr CMY200250KITM
Seachoice 95241
Sierra 18-6132
Tecnoseal 21104MG

Engine & Model Compatibility

Confirm your engine model and year in the table below. It is critical to verify the OEM part numbers match your service manual.

Brand Model Rated HP Stroke Years OEM Part No. Notes
Yamaha F200TXR 200 4-Stroke 6G5-45251-01M, 61A-45371-00M
Yamaha LF200TXR 200 4-Stroke 6G5-45251-01M, 61A-45371-00M
Yamaha V200TLXR 200 4-Stroke 6G5-45251-01M, 61A-45371-00M
Yamaha F225TXR 225 4-Stroke 6G5-45251-01M, 61A-45371-00M
Yamaha F225TUR 225 4-Stroke 6G5-45251-01M, 61A-45371-00M
Yamaha LF225TXR 225 4-Stroke 6G5-45251-01M, 61A-45371-00M
Yamaha LF225TUR 225 4-Stroke 6G5-45251-01M, 61A-45371-00M
Yamaha V225TXR 225 4-Stroke 6G5-45251-01M, 61A-45371-00M
Yamaha S225TXRX 225 4-Stroke 6G5-45251-01M, 61A-45371-00M
Yamaha F250TUR 250 4-Stroke 6G5-45251-01M, 61A-45371-00M
Yamaha F250TXR 250 4-Stroke 6G5-45251-01M, 61A-45371-00M
Yamaha LF250TXR 250 4-Stroke 6G5-45251-01M, 61A-45371-00M
Yamaha LF250TUR 250 4-Stroke 6G5-45251-01M, 61A-45371-00M
Yamaha S250TXRX 250 4-Stroke 6G5-45251-01M, 61A-45371-00M

Technical Specs

Product Type
Outboard Magnesium Anode Kit
Application
Fresh water only
Anode Material
High-purity magnesium alloy
Alloy Specification
US Military Specification (MIL-SPEC)
Installation
Bolt-on with included hardware
Product Dimensions
29.0 x 22.0 x 8.0 cm
Weight
0.597 kg (1.315 lb)
Hardware
Stainless steel mounting hardware included

What’s in the Box

  • 1 x Bracket Anode (Replaces 6G5-45251-01M)
  • 1 x Skeg Anode (Replaces 61A-45371-00M)
  • 1 x Set of Stainless Steel Mounting Hardware
  • 1 x Installation Instructions

Installation Notes

  1. Disconnect the engine's battery cables before beginning work.
  2. Locate and unbolt the old, depleted anodes from the trim tab housing and lower unit skeg.
  3. Thoroughly clean the mounting surfaces on the outboard. A wire brush is effective for removing any corrosion or residue to ensure a solid electrical connection.
  4. Align the new anodes and fasten them with the included stainless steel mounting hardware.
  5. Tighten the hardware securely, but do not overtighten, which could damage the threads or anode.
  6. Confirm the anodes are in firm contact with the metal of the motor. There should be no paint or sealant blocking this connection.
  7. Reconnect the battery cables and test operations.

Troubleshooting & FAQ

Can I use this magnesium anode kit in saltwater?

No. This kit is made of magnesium, which is only suitable for fresh water. Using it in salt or brackish water will cause it to corrode and dissolve extremely quickly, leaving your engine unprotected. For saltwater, use an aluminum alloy kit.

How do I know if this anode kit fits my Yamaha engine?

This kit is specifically for the Yamaha 200-250 HP four-stroke outboards listed. Please check the "Engine & Model Compatibility" table and cross-reference your engine's model number and original part numbers (6G5-45251-01M, 61A-45371-00M).

How often should I inspect and replace my anodes?

Anodes should be inspected at least once a year, or every 50-100 hours of use. We recommend replacement when they are 50% consumed or appear heavily pitted and corroded. Boats kept in the water require more frequent checks.

What are the signs that my anodes need replacement?

The most obvious sign is visible corrosion, crumbling, or "pitting" on the anode itself. If the anode has lost about half of its original mass, it's time for a replacement. A white, chalky coating is normal; significant physical decay is not.

OEM vs. Aftermarket?

This listing is an aftermarket replacement (not OEM). It's built to OEM-level specifications with comparable materials and manufactured in an ISO 9002 facility, where it is batch-inspected for consistency.

Shipping speed & cost?

We ship worldwide quickly—typical transit is 5–15 days. Standard shipping is free; expedited options appear at checkout where available.

Warranty & returns?

This product is covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window if the item is unused and in original condition. See our policy page or reach out for instructions.

Safety & Important Info

  • Verify images and 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.

About Sea Sierra

  • Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
  • Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
  • Manufacturer-Direct Value — Fair pricing without compromising on materials or quality control.

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