Water Pump Impeller Repair Kit – Fits Yamaha 9.9/15 HP (Replaces 682-W0078-A1-00)

Water Pump Impeller Repair Kit – Fits Yamaha 9.9/15 HP (Replaces 682-W0078-A1-00)

This water pump impeller repair kit is designed for Yamaha 9.9/15 HP 2-Stroke (1984–1995) and F9.9/T9.9 4-Stroke (1985–2005) outboard motors. It includes all the essential components required for a complete water pump service, ensuring your engine’s cooling system functions reliably.

This kit is a direct replacement for multiple OEM and aftermarket part numbers, including Yamaha 682-W0078-A1-00, 682-W0078-A2-00, 682-W0078-A3-00, Sierra 18-3148, Sierra 18-3411, Mariner 46-84277M, and 46-84277T.

• Installation Type: Direct replacement for specified outboard models.
• Complete Service Kit: Contains all necessary parts for a full water pump rebuild.
• Engine Compatibility: Fits both 2-stroke and 4-stroke Yamaha engines as listed.

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.

Yamaha 2-Stroke Applications

Yamaha 4-Stroke Applications

Technical Specifications

Installation Guide

1. Disconnect the battery and shift the outboard into the neutral position.
2. Remove the propeller and the bolts securing the lower unit (gearcase) to the upper driveshaft housing.
3. Carefully separate the lower unit from the engine assembly.
4. Unbolt and remove the water pump housing to expose the impeller. Note the rotational direction of the old impeller's fins.
5. Remove the old impeller, Woodruff key, gaskets, and wear plates. Thoroughly clean all surfaces of the housing and base.
6. Install the new gasket, wear plate, Woodruff key, and O-ring.
7. Apply a lubricant (silicone grease or dish soap) to the inside of the housing and the new impeller.
8. Install the new impeller, ensuring the fins are oriented in the correct rotational direction (typically clockwise).
9. Reinstall the water pump housing, tightening bolts to the manufacturer's specified torque.
10. Reattach the lower unit to the engine, ensuring the driveshaft, shift shaft, and water tube are properly aligned. Reinstall and tighten all bolts.

Troubleshooting & FAQ

How do I confirm this kit fits my Yamaha engine?
Check your engine's model and year against the 'Compatible Engine Models' table. This kit is specifically for Yamaha 9.9/15 HP 2-stroke models (1984–1995) and various F9.9/T9.9 4-stroke models (1985–2005). To be certain, use the provided Yamaha Serial Number Guide to identify your exact model.

What are the signs that my water pump impeller needs to be replaced?
Common signs of a failing impeller include the engine overheating, a weak or inconsistent water stream from the tell-tale outlet, or finding the existing impeller is cracked, brittle, or has deformed vanes during a routine inspection.

How often should I replace my water pump impeller?
As a crucial part of preventative maintenance, we recommend inspecting your impeller annually and replacing it every 1-2 years or every 100-200 hours of use. Service intervals may be shorter if you frequently operate in sandy, silty, or saltwater environments.

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.