Water Pump Impeller Kit – Fits Yamaha 40/50 HP 2-Stroke & F40/F50/F60 4-Stroke (Replaces Yamaha 63D-W0078-01-00, Sierra 18-3415, GLM 12276)
Water Pump Impeller Kit – Fits Yamaha 40/50 HP 2-Stroke & F40/F50/F60 4-Stroke (Replaces Yamaha 63D-W0078-01-00, Sierra 18-3415, GLM 12276) 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 63D-W0078-01-00, Sierra 18-3415, GLM 12276) is backordered and will ship as soon as it is back in stock.
Product Details
This Water Pump Impeller Kit – Fits Yamaha 40/50 HP 2-Stroke (1994-2005) & F40/F50/F60 4-Stroke (1996+) provides all necessary components to restore your engine's cooling system. It is engineered for a precise fit on Yamaha 2-stroke 40/50 HP (1994–2005) outboards, including C40, P40, C50, and P50 models, as well as 4-stroke F40 (1999), F50 (1997+), and F60 (2002+) models.
It serves as a direct replacement for Yamaha OEM part 63D-W0078-01-00 and its supersessions, along with aftermarket equivalents from Sierra (18-3415, 18-3434) and GLM (12276).
- Installs as a direct replacement for original factory components.
- Produced in an ISO 9002 certified facility for consistent quality.
- Includes all essential gaskets, seals, and hardware for a complete service.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket brands.
| Brand | Part Number | Notes |
|---|---|---|
| Yamaha | 63D-W0078-01-00 | Current OEM Number |
| Yamaha | 63D-W0078-03-00 | Superseded by 63D-W0078-01-00 |
| Yamaha | 63D-W0078-02-00 | Superseded by 63D-W0078-01-00 |
| Yamaha | 63D-W0078-00-00 | Superseded by 63D-W0078-01-00 |
| Sierra | 18-3415 | Aftermarket Interchange |
| Sierra | 18-3434 | Aftermarket Interchange |
| GLM | 12276 | Aftermarket Interchange |
Engine & Model Compatibility
Confirm your engine model and year in the tables below.
This kit is compatible with a range of Yamaha 2-stroke and 4-stroke outboard engines. Verify your specific model for a perfect fit.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. |
|---|---|---|---|---|---|
| Yamaha | 40 | 40 | 2-Stroke | 1995–2005 | 63D-W0078-01-00 |
| Yamaha | C40 | 40 | 2-Stroke | 1997–2003 | 63D-W0078-01-00 |
| Yamaha | P40 | 40 | 2-Stroke | 1998 | 63D-W0078-01-00 |
| Yamaha | 50 | 50 | 2-Stroke | 1998–2009 | 63D-W0078-01-00 |
| Yamaha | C50 | 50 | 2-Stroke | 1998–2001 | 63D-W0078-01-00 |
| Yamaha | P50 | 50 | 2-Stroke | 1995–1996 | 63D-W0078-01-00 |
| Yamaha | 40EJRV | 40 | 2-Stroke | 1997 | 63D-W0078-01-00 |
| Yamaha | 40EJRW | 40 | 2-Stroke | 1998 | 63D-W0078-01-00 |
| Yamaha | 40EJRX | 40 | 2-Stroke | 1999 | 63D-W0078-01-00 |
| Yamaha | 40ELRV | 40 | 2-Stroke | 1997 | 63D-W0078-01-00 |
| Yamaha | 40ELRW | 40 | 2-Stroke | 1998 | 63D-W0078-01-00 |
| Yamaha | 40TLRV/40TLRW/40TLRX/40TLRY/40TLRZ | 40 | 2-Stroke | 1997–2001 | 63D-W0078-01-00 |
| Yamaha | 40TLRA/40TLRB/40TLRC/40TLRD | 40 | 2-Stroke | 2002–2005 | 63D-W0078-01-00 |
| Yamaha | 50TLRA/50TLRB/50TLRC/50TLRD | 50 | 2-Stroke | 2002–2005 | 6D-W0078-01-00 |
| Yamaha | T50TLRC/T50TLRV | 50 | 2-Stroke | 1997–2004 | 63D-W0078-01-00 |
| Yamaha | F40 | 40 | 4-Stroke | 1999 | 63D-W0078-01-00 |
| Yamaha | F40TLRX | 40 | 4-Stroke | 1999 | 63D-W0078-01-00 |
| Yamaha | F50 | 50 | 4-Stroke | 1997+ | 63D-W0078-01-00 |
| Yamaha | F50TLRV/F50TLRW/F50TLRX/F50TLRY/F50TLRZ | 50 | 4-Stroke | 1997–2001 | 63D-W0078-01-00 |
| Yamaha | F50TLRA/F50TLRB/F50TLRC/F50TLRD | 50 | 4-Stroke | 2002–2005 | 63D-W0078-01-00 |
| Yamaha | F50LA/F50LB | 50 | 4-Stroke | 2011–2016 | 63D-W0078-01-00 |
| Yamaha | F60 | 60 | 4-Stroke | 2002+ | 63D-W0078-01-00 |
| Yamaha | F60TLRA/F60TLRB/F60TLRC/F60TLRD | 60 | 4-Stroke | 2002–2005 | 63D-W0078-01-00 |
| Yamaha | F60JB/F60LA/F60LB | 60 | 4-Stroke | 2011–2016 | 63D-W0078-01-00 |
| Yamaha | F60TJR series | 60 | 4-Stroke | 2003–2007 | 63D-W0078-01-00 |
Technical Specs
- Product Type
- Water Pump Impeller Kit
- Installation
- Direct replacement for OEM components
- Quality Certification
- ISO9002 certified factory production (JLM Marine)
What’s in the Box
- 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 2 (663-44366-00-00)
- 1 x Woodruff Key (90280-03024-00)
Installation Notes
- Disconnect the battery and ensure the engine is fully cooled before starting.
- Drain the lower unit gear lube.
- Remove the propeller and unbolt the lower unit (gearcase) from the upper engine casing.
- Carefully lower and remove the gearcase, making sure to disconnect the speedometer tube if present.
- Unbolt and remove the old water pump housing. Note the orientation of the old parts.
- Clean the mounting surfaces and inspect the driveshaft.
- Install the new gasket, outer plate, impeller (rotate shaft clockwise), and housing from the kit.
- Apply marine grease to the new housing and bolt threads. Torque bolts to manufacturer specifications.
- Reassemble the lower unit to the engine, ensuring the water tube, shift shaft, and driveshaft align correctly.
- Refill the gearcase with fresh lube, reinstall the propeller, and reconnect the battery.
- Test the engine in water, confirming a steady stream of water from the tell-tale port.
Troubleshooting & FAQ
How do I know if my water pump impeller needs replacing?
Common signs of a failing impeller include a weak or inconsistent water stream from the tell-tale port, rising engine temperature at idle or low speeds, or an engine overheat alarm. It is a critical maintenance item that should be replaced proactively.
What is the recommended replacement interval for an impeller?
For most Yamaha outboards, it is recommended to inspect the impeller annually and replace it every 1-2 years or 100-200 operating hours, whichever comes first. Usage in saltwater or silty/sandy conditions may require more frequent changes.
My engine is still overheating after installing the new kit. What should I check?
If overheating persists, verify that all cooling passages are clear of debris, the thermostat is functioning correctly, and the water intake screens are unobstructed. Also, ensure the water tube was properly aligned with the pump outlet during reassembly.
How do I confirm this kit will fit my specific Yamaha engine?
The most reliable method is to match your engine's full model and year to our compatibility list. You can also cross-reference your existing part number with the numbers listed in our Part Number Matrix.
Is there a difference in performance between this kit and the OEM version?
This aftermarket kit is designed and manufactured to meet or exceed OEM specifications. It provides a comparable level of performance, durability, and cooling efficiency to the original Yamaha parts but at a more accessible price point.
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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