Water Pump Impeller Kit – Fits Yamaha 40-50 HP 2-Stroke & F40/F50/F60 4-Stroke (Replaces Yamaha, Sierra)
Water Pump Impeller Kit – Fits Yamaha 40-50 HP 2-Stroke & F40/F50/F60 4-Stroke (Replaces Yamaha, Sierra) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
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Water Pump Impeller Kit – Fits Yamaha 40-50 HP 2-Stroke & F40/F...
Water Pump Impeller Kit – Fits Yamaha 40-50 HP 2-Stroke & F40/F50/F60 4-Stroke (Replaces Yamaha, Sierra) is backordered and will ship as soon as it is back in stock.
Product Details
This complete Water Pump Impeller Kit – Fits Yamaha 40-50 HP 2-Stroke & F40/F50/F60 4-Stroke (Replaces 63D-W0078-01-00) provides all necessary components to rebuild your outboard's water pump. It is designed for reliable performance in Yamaha 40-50 HP 2-Stroke (1994–2005) and F40/F50/F60 4-Stroke (1996+) engines.
It serves as a direct replacement for Yamaha part numbers 63D-W0078-01-00, 63D-W0078-02-00, and Sierra 18-3370.
- Engineered for direct-fit installation, simplifying maintenance.
- Includes the essential impeller, housing, gaskets, and O-ring for a full service.
- Constructed with a durable composite housing and a robust neoprene impeller for longevity.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Yamaha | 63D-W0078-01-00 |
| Yamaha | 63D-W0078-02-00 |
| Sierra | 18-3370 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
Fits the following Yamaha 2-stroke and 4-stroke outboard models.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Yamaha | F40 | 40 | 4-Stroke | 1996+ | 63D-W0078-01-00 | 747cc, 3-cylinder |
| Yamaha | F50 | 50 | 4-Stroke | 1996+ | 63D-W0078-01-00 | 747cc, 3-cylinder |
| Yamaha | F60 | 60 | 4-Stroke | 1996+ | 63D-W0078-01-00 | 747cc, 3-cylinder |
| Yamaha | 40 | 40 | 2-Stroke | 1994–2005 | 63D-W0078-01-00 | |
| Yamaha | 50 | 50 | 2-Stroke | 1994–2005 | 63D-W0078-01-00 |
Technical Specs
- Product Type
- Water Pump Impeller Kit
- Installation
- Direct Replacement
- Housing Material
- Plastic/Composite
- Housing Color
- Black
- Impeller Material
- Rubber/Neoprene
- Kit Components
- Includes complete rebuild components (impeller, housing, gaskets, O-ring)
- Warranty
- Limited 3-year Pleasure/Government, 1-Year Commercial
What’s in the Box
- 1 x Water Pump Impeller (63D-W0078-01-00)
- 1 x Housing
- 1 x Metal Cup
- 1 x Gasket
- 1 x O-Ring
Installation Notes
- Disconnect the battery and shift the outboard to the neutral position.
- Remove the lower unit bolts and carefully separate the lower unit from the engine.
- Unbolt and remove the old water pump housing and impeller assembly.
- Clean the mounting surfaces, ensuring they are free of old gasket material and debris.
- Install the new metal cup, impeller, and housing, applying a light marine grease to the impeller.
- Reinstall the lower unit, ensuring the driveshaft and water tube align correctly. Fasten all bolts to the manufacturer's torque specifications.
- Reconnect the battery and test the engine in the water, verifying water is exiting the tell-tale port.
Troubleshooting & FAQ
How do I know if this kit fits my Yamaha outboard?
This kit is designed for Yamaha 40-50 HP 2-Stroke engines (1994–2005) and F40/F50/F60 4-Stroke models (1996+). Please verify your engine's model and year against our compatibility table before ordering.
What are the signs of a failing water pump impeller?
Common signs include a weak or non-existent water stream from the tell-tale port, engine overheating alarms, and a noticeable decrease in engine performance. If you notice any of these symptoms, inspect your water pump immediately.
How often should the water pump impeller be replaced?
For preventative maintenance, it is recommended to inspect the impeller annually and replace it every 1-3 years, depending on usage hours and water conditions (e.g., saltwater, silty water).
OEM vs. Aftermarket?
This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.
Shipping speed & cost?
We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.
Warranty & returns?
Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.
Safety & Important Info
- Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
- This is an aftermarket replacement, not an OEM component.
- Professional installation is recommended for safety and performance.
About Sea Sierra
- Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
- Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
- Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.
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