Water Pump Impeller Kit – Fits Yamaha F9.9/F13.5/F15/F20 Outboard Motors (Replaces 6AH-W0078-00-00)

Water Pump Impeller Kit – Fits Yamaha F9.9/F13.5/F15/F20 Outboard Motors

This water pump impeller service kit is designed for a wide range of Yamaha 4-stroke outboard engines, including 9.9 HP, 13.5 HP, 15 HP, and 20 HP models from 2006 to 2023. It contains all the necessary components for a complete and reliable water pump rebuild, ensuring your engine maintains proper cooling.

It serves as a direct replacement for Yamaha OEM part numbers 6AH-W0078-00-00, 6AH-W0078-01-00, and 6AH-W0078-02-00, as well as Sierra part number 18-3479.

• Complete Repair Kit: Includes the impeller, housing, plates, gaskets, and hardware required for a full service.
• Broad Compatibility: Fits various Yamaha outboards, including F9.9, F13.5, F15, F15C, and F20 models.
• Installation Location: Mounts on the lower unit of the outboard motor.

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 Water Pump Housing (6AH-44311-00-00)
• 1 x Cartridge Insert (63V-44322-00-00)
• 1 x Water Seal Damper (6L2-44367-00-00)
• 1 x Impeller (63V-44352-01-00)
• 1 x Woodruff Key (664-44338-00-00)
• 1 x O-Ring (93210-49046-00)
• 1 x Cartridge Outer Plate (68T-44323-00-00)
• 2 x Dowel Pin (93604-10M03-00)
• 4 x Bolt (97095-08045-00)
• 2 x Plate (63V-44328-01-00)

Installation Guide

1. Disconnect the battery and uncouple the shift linkage.
2. Unbolt and carefully remove the lower unit from the outboard motor.
3. Locate and unbolt the existing water pump housing.
4. Lift the old water pump assembly off the driveshaft, noting the orientation of all parts.
5. Thoroughly clean the mounting surfaces, removing any old gasket material or debris.
6. Slide the new Woodruff key and impeller onto the driveshaft.
7. Assemble the new housing, cartridge, seals, and plates as per the diagram.
8. Secure the new pump housing with the provided bolts, torquing them to manufacturer specifications.
9. Re-install the lower unit onto the outboard leg.
10. Reconnect the shift linkage and battery terminals.
11. Attach a water supply and run the engine at idle to confirm a steady "tell-tale" stream.

Troubleshooting & FAQ

How do I confirm this fits my engine?
Verify your engine's model and year in the "Compatible Engine Models" table. This kit is a direct replacement for OEM part number 6AH-W0078-00-00 and fits a wide range of Yamaha F9.9 to F20 models. Cross-referencing your existing part number is the best way to ensure a correct fit.

What are the signs of a failing water pump?
Common symptoms include the engine overheating at idle or low speeds, a weak or intermittent water stream from the "tell-tale" outlet, or an alarm from your engine's warning system. Visible cracks, missing vanes, or brittleness on the old impeller are clear indicators for replacement.

How often should I replace the water pump impeller?
For preventative maintenance, we recommend inspecting the impeller annually and replacing it every 1-2 years or 100-200 hours of operation. Service intervals should be shorter if operating frequently in saltwater, or shallow, sandy/silty water.

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.