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

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

This water pump impeller repair kit provides a complete solution for servicing Yamaha 40 HP, 50 HP, and 60 HP outboard motors (2-stroke and 4-stroke models, 1995–present). It is engineered to meet or exceed OEM specifications for reliable performance.

This kit is a direct replacement for Yamaha part numbers 63D-W0078-00-00 and 63D-W0078-01-00, as well as aftermarket equivalents from Sierra, GHmarine, and GlückMarine.

• Complete Kit: Includes a neoprene impeller, stainless steel housing components, gaskets, and hardware for a full rebuild.
• Direct Fit: Designed for straightforward installation without modifications.
• Durable Materials: Features a high-performance neoprene impeller and corrosion-resistant housing for longevity.

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 Neoprene Impeller (6H3-44352-00)
• 1 x Wear Plate (63D-44323-00)
• 1 x Insert Cup (63D-44322-00)
• 1 x Gasket (63D-44316-00)
• 1 x O-Ring (93210-59MG7)
• 1 x Woodruff Key (90280-03024)
• 1 x Cover, Water Pump Housing (63D-44312-00)
• 1 x Grommet (663-44366-00)
• 4 x Installation bolt and washer (90119-08M15)

Installation Guide

1. Disconnect Power: Start by disconnecting the battery.
2. Drain Gear Lube: Drain the gear lube from the lower unit to prevent spills.
3. Remove Lower Unit: Unbolt and carefully detach the lower unit (gearcase) from the outboard's main housing.
4. Access Pump: Unscrew the bolts holding the water pump housing and remove it to expose the impeller.
5. Inspect & Remove Old Parts: Note the rotational direction of the old impeller's blades before removing it, along with the housing, plate, cup, and gaskets.
6. Clean Surfaces: Thoroughly clean all mating surfaces to ensure a proper seal with the new components.
7. Install New Components: Install the new gasket, wear plate, insert cup, and woodruff key.
8. Install New Impeller: Slide the new impeller onto the driveshaft, twisting it in the same direction as the original to correctly seat the vanes.
9. Reassemble Pump: Apply the new O-ring, reinstall the housing cover, and tighten the bolts to the specified torque.
10. Reattach Lower Unit: Reinstall the lower unit onto the outboard and refill it with fresh gear lube.
11. Test Operation: Before heading out, connect a water supply (flushing muffs) to the engine, start it, and confirm a steady stream from the tell-tale outlet.

Troubleshooting & FAQ

Q: How do I confirm this fits my engine?

A: First, check your engine model, horsepower, and year against the detailed compatibility table above. For Yamaha owners, use the linked Serial Number Guide to find your exact model information. This kit directly replaces OEM part numbers 63D-W0078-00-00 and 63D-W0078-01-00; cross-referencing this number is the most reliable way to ensure a match.

Q: How often should I replace the water pump impeller?

A: For optimal engine protection, we recommend inspecting the impeller annually. It should be replaced every 1-2 years or every 100-200 hours of use. Replacement frequency depends on operating conditions; engines used in saltwater or sandy/silty water may require more frequent service.

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

A: The most common signs include the engine running hotter than normal or an overheating alarm, a weak or non-existent water stream from the "tell-tale" cooling outlet, and steam from the exhaust. During inspection, a damaged impeller may have brittle, cracked, or melted vanes.

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.