Water Pump Impeller Repair Kit – Fits Yamaha 50-70 HP Outboards (Replaces 6H3-W0078-A0-00, 6H3-W0078-02-00)

Water Pump Impeller Repair Kit – Fits Yamaha 50-70 HP Outboards (Replaces 6H3-W0078-A0-00, 6H3-W0078-02-00)

This aftermarket water pump impeller repair kit is designed for Yamaha 2-Stroke 60–70 HP (1997–2003) and 4-Stroke 50–60 HP High Thrust (1997–present) outboard motors. It provides an essential solution for lower unit water pump maintenance and rebuilds.

Direct replacements include Yamaha part numbers 6H3-W0078-00-00, 6H3-W0078-01-00, 6H3-W0078-02-00, 6H3-W0078-A0-00, as well as Sierra numbers 18-3466, 18-3461, and 18-3428-1.

• Complete water pump rebuild kit including impeller, gaskets, and hardware
• Fits installation on lower unit
• Compatible with both 2-Stroke and 4-Stroke Yamaha models

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. For Yamaha owners, here's a guide to help you identify your engine's serial/model: Yamaha Serial Number Guide. You can also review exploded diagrams to verify part numbers: Yamaha Parts Diagrams & Catalog.

Technical Specifications

Package Contents

• 1 x Cartridge Insert (663-44322-00-00)
• 1 x Impeller (6H3-44352-01/697-44352-00)
• 1 x Water Pump Gasket (6H3-44315-A0-00)
• 1 x Cartridge Outer Plate/Wear Plate (6H3-44323-00-00)
• 1 x Cartridge Gasket (6H3-44324-A0-00)
• 1 x Water Pump Gasket (688-44316-A0-00)
• 1 x O-Ring (93210-46044-00)
• 2 x Bolts (97095-08045-00)
• 2 x Bolts (97395-08055-00)
• 1 x Woodruff Key (90280-03M03-00)

Installation Guide

1. Remove the lower unit from the outboard motor following manufacturer safety guidelines.
2. Drain any remaining water from the lower unit before disassembly.
3. Remove the old water pump housing and impeller carefully to avoid damage to surrounding parts.
4. Inspect the housing and replace any damaged parts as necessary.
5. Install the new impeller and associated gaskets included in the kit.
6. Replace the cartridge insert, outer plate, and gaskets in proper order.
7. Secure all bolts and hardware to manufacturer torque specifications.
8. Reinstall the lower unit onto the outboard motor.
9. Test operation to ensure proper water flow and no leaks.

Troubleshooting & FAQ

How do I confirm this fits my engine?

Check the compatible engine models table for your model and year. Use the Yamaha Serial Number Guide linked above to verify your engine details.

What are the differences between this aftermarket kit and OEM parts?

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 often should I replace the water pump impeller?

It is recommended to inspect and replace the water pump impeller at least once per boating season or every 100 hours of operation, whichever comes first.

What are common signs of water pump failure?

Reduced water flow from the cooling system, engine overheating, and unusual noises may indicate water pump failure or impeller damage.

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.