Water Pump Repair Kit – Fits Yamaha 40-60HP Outboards (Replaces 63D-W0078-01-00)

Water Pump Repair Kit – Fits Yamaha 40-60HP Outboards (Replaces 63D-W0078-01-00)

This water pump repair kit provides all the necessary components to restore the cooling system on a wide range of Yamaha 40HP, 50HP, and 60HP outboard engines. It is designed to meet or exceed OEM specifications for reliable performance and longevity.

This kit is a direct replacement for Yamaha part numbers 63D-W0078-01-00, 63D-W0078-03-00, and 63D-W0078-00-00.

• Fits select Yamaha 2-Stroke C40, P40, C50, and P50 models (1997–2005).
• Compatible with Yamaha 4-Stroke F40, F50, and F60 models (1997 and newer).
• Includes a complete housing, impeller, gaskets, and hardware for a full lower unit water pump overhaul.

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 Outboards (2-Stroke)

Yamaha Outboards (4-Stroke)

Technical Specifications

Package Contents

• 1 x Cartridge Insert (63D-44322-00-00)
• 1 x Impeller (6H3-44352-00-00)
• 1 x Water Pump Housing Cover (63D-44312-00-00)
• 1 x Cartridge Outer Plate (63D-44323-00-00)
• 1 x O-Ring (93210-59MG7-00)
• 1 x Water Pump Gasket (63D-44316-00-00)
• 4 x Bolts With Washers (90119-08M15-00)
• 1 x Water Seal Damper (663-44366-00-00)
• 1 x Woodruff Key (90280-03024-00)

Installation Guide

1. Disconnect the battery and remove the spark plug wires for safety.
2. Place a drain pan under the lower unit and remove the gearcase oil drain screw to empty the oil.
3. Remove the mounting bolts securing the lower unit (gearcase) to the upper casing and carefully lower it.
4. Unscrew the bolts from the top of the existing water pump housing.
5. Slide the old housing, impeller, gaskets, and wear plates off the driveshaft.
6. Thoroughly clean the driveshaft and all mating surfaces where the new components will sit.
7. Install the new gasket and outer plate onto the lower unit.
8. Slide the new Woodruff key into its slot on the driveshaft, followed by the new impeller.
9. Apply marine grease to the inside of the new pump housing and install it over the impeller.
10. Fasten the housing with the new bolts and torque them to the manufacturer's specifications.
11. Re-install the lower unit, refill with fresh gearcase oil, and reconnect the battery.
12. Test the engine using a water supply (flushing muffs) to confirm proper water circulation.

Troubleshooting & FAQ

Q: How do I confirm this kit will fit my Yamaha engine?

A: The best way is to locate your engine's model and serial number. Then, use our "Compatible Engine Models" tables above to find your specific model and year. Verifying the part number 63D-W0078-01-00 in your engine's service manual or parts diagram also guarantees a match.

Q: What are the common signs of a failing water pump?

A: The most common indicators are engine overheating alarms and a weak or non-existent stream of water from the "tell-tale" pilot water outlet. Reduced top-end performance can also be a symptom.

Q: How often should I replace my outboard's water pump impeller?

A: As a general rule of thumb, it is recommended to replace the water pump impeller and gaskets annually or every 100 hours of operation, whichever comes first. This preventative maintenance is critical for engine health.

Q: Does this kit include everything I need for the installation?

A: This kit includes all the direct replacement parts for the water pump assembly itself. However, you will need your own tools and consumables like marine grease, which is highly recommended for lubrication during assembly but not included.

Q: OEM vs. Aftermarket?

A: 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.

Q: How fast do you ship and how much does it cost?

A: 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.

Q: What is your warranty and return policy?

A: 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.