Water Pump Impeller – Fits Yamaha 40HP Outboard Engines (Replaces 6F5-44352-01, 676-44352-00)

Water Pump Impeller – Fits Yamaha 40HP Outboard Engines (Replaces 6F5-44352-01, 676-44352-00)

This water pump impeller is designed for Yamaha 2-Stroke 40HP (C40, CV40) outboard engines, covering models from the 1990s to 2005. It serves as a direct replacement, ensuring proper fit and function for routine cooling system maintenance.

This component is a direct replacement for Yamaha part numbers 6F5-44352-01 and 676-44352-00. It also cross-references with Sierra 18-3088 and Mercury/Mariner 47-99971M.

• Installation Type: Direct Replacement
• Primary Material: Durable Neoprene Rubber
• Package Contents: 1x Water Pump Impeller

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 Impeller (6F5-44352-01/676-44352-00)

Installation Guide

1. Disconnect the battery and shift linkage before starting.
2. Remove the bolts securing the lower unit and carefully lower the gearcase.
3. Unscrew the bolts on the water pump housing and lift it off.
4. Note the rotational direction of the old impeller's blades as you remove it.
5. Slide the old impeller off the driveshaft, removing the key.
6. Clean the housing interior and inspect all surfaces for wear or damage.
7. Apply a light coat of marine grease to the new impeller and the inside of the housing.
8. Install the new key and slide the new impeller onto the driveshaft.
9. While pushing down on the housing, turn the driveshaft clockwise to seat the blades correctly.
10. Reinstall the housing and tighten the bolts to the manufacturer's specified torque.
11. Reattach the lower unit and reconnect the shift linkage.
12. Test the engine on a water supply to ensure a strong stream from the tell-tale.

Troubleshooting & FAQ

How do I confirm this fits my engine?
First, cross-reference your existing part number with those listed in our table (e.g., Yamaha 6F5-44352-01, Sierra 18-3088). Second, verify your engine model and year against the "Compatible Engine Models" list. If you are unsure, use the provided guides to find your serial number.

What are the signs of a failing impeller?
The most common symptoms are an overheating engine, especially at idle, or a weak or non-existent water stream from the "tell-tale" outlet. Reduced engine performance can also be a sign.

How often should I replace the impeller?
For most recreational boats, it's recommended to replace the water pump impeller every 1 to 2 years or every 100-200 hours of use. This can vary based on usage and water conditions (e.g., saltwater or sandy environments may require more frequent changes).

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.