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Yanmar Stern Drive Zinc Anode Kit – Fits Yanmar ZT350-ZT370 (Replaces TENKITYANMARSTD)

Regular price $99.99

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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 Yanmar Stern Drive Zinc Anode Kit provides essential corrosion protection for Yanmar ZT350 and ZT370 series stern drives. Made from high-grade zinc, it is designed for use in saltwater environments to safeguard underwater metallic components from galvanic corrosion.

This kit serves as a direct replacement for TecnoSeal part number TENKITYANMARSTD.

  • Designed for external mounting on the stern drive.
  • Provides critical galvanic corrosion protection.
  • Cast from military-specification zinc alloy for reliable performance.

Engine & Model Compatibility

Confirm your engine model in the table below. This kit is specifically designed for the following Yanmar stern drives.

Brand Model OEM Part No. Notes
Yanmar ZT350 TENKITYANMARSTD Stern drive anode kit
Yanmar ZT370 TENKITYANMARSTD Stern drive anode kit

Technical Specs

Product Type
Zinc Anode Kit
Installation
External mount on stern drive
Connection
Direct mounting to stern drive
Housing Material
Zinc
Housing Color
Metallic gray (zinc)
Dimensions
Length: 32.5 cm, Width: 22.5 cm, Height: 8.0 cm
Weight
2.68 kg (5.91 lbs)
Fitting Type
Direct mount
Other Technical Attributes
Corrosion protection for stern drive

Installation Notes

  1. Haul the vessel out of the water and ensure it is safely and securely supported.
  2. Locate and unbolt the existing, depleted anodes from the stern drive housing. You may need to clean the area to access the fasteners.
  3. Thoroughly clean the mounting surfaces on the stern drive where the new anodes will sit. A wire brush is effective for removing fouling and oxidation to ensure direct metal-to-metal contact.
  4. Position the new zinc anodes from the kit onto the cleaned surfaces and securely fasten them with the appropriate hardware. Do not overtighten.
  5. Never apply paint, anti-fouling coatings, or any other finish to the surface of the anodes or their mounting fasteners, as this will prevent them from functioning correctly.
  6. Once all anodes are installed, the vessel can be returned to the water.

Troubleshooting & FAQ

How do I know if this anode kit is the right one for my boat?

This kit is specifically designed for Yanmar ZT350 and ZT370 stern drives. Please verify your stern drive model before purchasing. Using the wrong anode type or shape can lead to inadequate protection.

Why use zinc anodes instead of aluminum or magnesium?

Zinc anodes are the industry standard for protecting vessels in saltwater. Aluminum anodes are typically used for brackish water, and magnesium anodes are reserved for freshwater only. Using the wrong material for the water type can result in either rapid depletion or inadequate protection.

How often should I inspect and replace my stern drive anodes?

Anodes should be inspected at least once a year, or every time the boat is hauled out. Replace them when they are approximately 50% consumed. Do not wait for them to disappear completely, as this leaves your drive unprotected.

What are the signs that my anodes are failing or need replacement?

The most obvious sign is visual erosion—the anode will appear pitted and reduced in size. If you notice new or accelerated corrosion on other underwater metal parts, such as your propeller or trim tabs, it's a strong indication that your anodes are depleted or not making proper electrical contact.

Can I paint my anodes to make them last longer?

No. Never paint an anode. Anodes work through galvanic corrosion, sacrificing themselves to protect other metals. A layer of paint will insulate the anode, rendering it completely ineffective and exposing your expensive stern drive components to corrosive damage.

Is it normal for the new anode to look different from the old, eroded one?

Yes. A new anode will appear smooth and solid. A used anode will be pitted, eroded, and significantly smaller. This erosion is a sign that the anode has been doing its job correctly by sacrificing itself to protect the more valuable components of your stern drive.

OEM vs. Aftermarket?

This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.

Shipping speed & cost

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

Warranty & returns

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 (unused & in original condition). See our policy page or reach out for instructions.

Safety & Important Info

  • Verify images/specifications vs 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 QC.

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