Zinc Anode Rod Set – Fits Volvo Penta D4-D6 and TAMD Series (Replaces 838929, 804107, 800476)

Zinc Anode Rod Set – Fits Volvo Penta D4-D6 and TAMD Series

This zinc pencil anode set is designed for sacrificial cathodic protection in Volvo Penta marine diesel engines. Specifically engineered for use in raw water cooling systems, it helps protect vital metal components from galvanic corrosion, which is common in saltwater environments.

This kit is a direct replacement for multiple Volvo Penta part numbers, including 838929, 804107, 800476, 858501, and 3838499. It also cross-references with aftermarket parts like Sierra 18-6001, GLM 12789, CMP CM838929Z, and Tecnoseal 00714.

• Material: High-grade zinc designed for optimal performance in saltwater.
• Installation: Features a 7/16" UNC external thread and M8 internal thread for easy installation.
• Package Contents: Includes 5 x Zinc Pencil Anodes (838929).

Part Number Cross-Reference

Use this table to confirm equivalent part numbers across OEM and aftermarket brands.

Compatible Engine Models

Confirm your engine model/year in the table below.

Technical Specifications

Package Contents

• 5 x Zinc Pencil Anode (Replaces 838929)

Installation Guide

1. Before starting, ensure the engine is off and has cooled down. Close the corresponding seacock to prevent water from entering the vessel.
2. Locate the existing zinc anode plug on your engine's cooling system. It is typically found on the heat exchanger, oil cooler, or aftercooler.
3. Carefully drain the cooling system component where the anode is located to avoid spillage.
4. Use an appropriate wrench to unscrew and remove the old anode plug. The old anode may be heavily corroded or completely gone.
5. Clean the threads of the plug housing thoroughly to ensure a good connection and prevent leaks.
6. Screw the new zinc anode into the housing by hand until it is snug.
7. Use a wrench to tighten the plug securely, but do not overtighten as this can damage the threads or the plug.
8. Once the new anode is installed, re-open the seacock.
9. Start the engine and carefully inspect the area around the new anode plug for any signs of water leaks.

Troubleshooting & FAQ

How do I confirm this anode fits my engine?

Please review the Compatible Engine Models table on this page to see if your specific model is listed. You should also cross-reference your existing part number with the numbers in our Part Number Cross-Reference table to ensure an exact match.

How often should I replace my zinc anode?

Inspection intervals can vary based on usage and water conditions, but a general rule is to check your anodes every 3-6 months. The anode should be replaced when it is approximately 50% consumed to ensure continuous protection.

What are the signs of a failing or depleted anode?

If an anode is depleted, galvanic corrosion will attack other metal components in the cooling system, such as the heat exchanger core. Signs include premature corrosion, pitting, or rust on these parts. Regular inspection is key to preventing this damage.

OEM vs. Aftermarket?

This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.

How fast do you ship and how much does it cost?

We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.

What is your warranty and return policy?

This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused & in original condition); please see our policy page or reach out for instructions.

Important Notes

• Verify that the product images and specifications match your original part. If discrepancies exist—even if your model is listed—do not proceed with the purchase.
• This product is an aftermarket replacement part and is not an OEM component.
• Professional installation is recommended to ensure safety and optimal performance.

Why Choose JLM MARINE?

• Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
• Fast Global Shipping: Free delivery worldwide in 5–15 days.
• Direct from Manufacturer: Competitive pricing without compromising quality.