Water Pump Repair Kit – Fits Yamaha 40HP 2-Stroke (Replaces 679-W0078-A1-00, 6F5-W0078-A0-00)

Water Pump Repair Kit – Fits Yamaha 40HP 2-Stroke (Replaces 679-W0078-A1-00, 6F5-W0078-A0-00)

This water pump repair kit provides the necessary components for servicing the water pump on Yamaha 40HP 2-Stroke C40 and CV40 models from 1990 to 1997. It is also compatible with select Mariner 40HP 2-Stroke outboards.

This kit is a direct replacement for multiple OEM and aftermarket part numbers, ensuring a precise fit and restoring cooling system performance. Please verify your engine model and part number before ordering.

• Direct Installation: Designed to meet or exceed OEM specifications for a direct fit.
• Complete Service Kit: Includes all necessary gaskets, seals, impeller, and hardware for a full water pump service, excluding the housing.

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

Mariner

Technical Specifications

Package Contents

• 1 × Water Seal (663-44366-00-00)
• 1 × Water Pump Gasket (676-44315-A0-00/676-44315-A1-00)
• 1 × Insert Cup (676-44322-00-00)
• 1 × Outer Plate, Cartridge (676-44323-00-00)
• 1 × Cartridge Gasket (676-44324-A0-00/676-44324-A1-00)
• 1 × Water Pump Gasket (679-44316-A0-00/679-44316-A1-00)
• 1 × Impeller (6F5-44352-00-00)
• 1 × Woodruff Key (90280-04M00-00)
• 4 × Washer, Plain (92990-08600-00)
• 2 × Bolt, Hexagon (97095-08045-00)
• 2 × Bolt, Hexagon (97095-08055-00)

Installation Guide

1. Disconnect the battery leads and remove the engine cover.
2. Shift the outboard into neutral and remove the lower unit mounting bolts.
3. Carefully lower and separate the lower unit from the upper casing.
4. Unbolt and remove the water pump housing to access the impeller and other components.
5. Remove the old impeller, gaskets, wear plate, and seals, noting their orientation.
6. Thoroughly clean all mating surfaces, removing any old gasket material or residue.
7. Install the new cartridge gasket, outer plate, insert cup, and water seal from the kit.
8. Apply a light coat of marine grease to the new impeller and slide it onto the driveshaft, turning clockwise to seat the vanes.
9. Install the new water pump gaskets and securely reinstall the housing.
10. Reattach the lower unit to the outboard, ensuring the driveshaft and water tube align correctly.
11. Tighten all bolts to the manufacturer's recommended torque specifications.
12. Reconnect the battery and test the engine with a water supply to verify proper cooling system operation.

Troubleshooting & FAQ

How do I confirm this kit fits my Yamaha engine?

This kit is designed for Yamaha 40HP 2-Stroke C40 and CV40 models from 1990-1997. Please check your specific model number against the compatibility table provided on this page. For help finding your model number, refer to our Yamaha Serial Number Guide.

What are the signs that my water pump needs to be replaced?

Common signs of a failing water pump include the engine overheating, a weak or inconsistent water stream from the "tell-tale" outlet, or visible damage to the old impeller, such as cracked or missing vanes.

How often should I service my water pump?

It is generally recommended to inspect and replace your water pump impeller and gaskets every 1-2 years or every 100-200 hours of use, depending on operating conditions (e.g., saltwater vs. freshwater).

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.