Water Pump Impeller Kit with Pump Cover for Yamaha 40/50 HP 2-Stroke and F40/F50/F60 4-Stroke – Replaces 63D-W0078-01-00
Water Pump Impeller Kit with Pump Cover for Yamaha 40/50 HP 2-Stroke and F40/F50/F60 4-Stroke – Replaces 63D-W0078-01-00 is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
Orders are typically processed within 1–2 business days.
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Water Pump Impeller Kit with Pump Cover for Yamaha 40/50 HP 2-Strok...
Water Pump Impeller Kit with Pump Cover for Yamaha 40/50 HP 2-Stroke and F40/F50/F60 4-Stroke – Replaces 63D-W0078-01-00 is backordered and will ship as soon as it is back in stock.
Product Details
This aftermarket water pump impeller kit with pump cover is designed to service the cooling system on selected Yamaha 40 and 50 HP 2-stroke outboards and F40, F50, and F60 4-stroke outboards. It replaces the Yamaha water pump repair kit reference 63D-W0078-01-00 and is intended for direct replacement of the listed water pump service components.
Catalog references associate this kit with Yamaha 40/50 HP 2-stroke applications, including selected C40 and P40 models, and selected F40, F50, P50, and F60 4-stroke applications. Always compare your complete engine model, year, and existing part number before ordering because fitment can vary by model configuration and production year.
- Complete water pump service kit for the listed Yamaha applications.
- Includes an impeller, pump cover, wear plate, insert cup, seals, gasket, key, bolts, washers, and O-ring.
- Aftermarket replacement; not an OEM Yamaha component.
- Produced in an ISO 9002-certified facility according to the supplied product information.
Part Number Matrix
Use these verified reference numbers to compare the kit with your original part and other aftermarket catalogs. Reference numbers are provided for identification and interchange research only.
| Brand | Part Number | Notes |
|---|---|---|
| Yamaha | 63D-W0078-01-00 | OEM reference |
| Yamaha | 63D-W0078-00-00 | Earlier water pump repair kit reference found in catalog listings |
| Yamaha | 63D-W0078-02-00 | Catalog cross-reference |
| Yamaha | 63D-W0078-03-00 | Later catalog application reference; verify the complete engine model and year |
| Sierra | 18-3415 | Aftermarket cross-reference for the kit with pump cover |
| Sierra | 18-3434 | Aftermarket cross-reference listed for the related kit configuration |
| GLM | 12276 | Aftermarket cross-reference |
Engine & Model Compatibility
The following applications are identified in the available Yamaha and aftermarket catalog references. Match the complete model designation and year before installation.
| Brand | Model or Family | Rated HP | Stroke | Catalog Years or Conditions | OEM Reference |
|---|---|---|---|---|---|
| Yamaha | 40 and 50 HP | 40–50 | 2-Stroke | Selected 1995–2003 applications | 63D-W0078-01-00 |
| Yamaha | C40, 3-cylinder | 40 | 2-Stroke | Selected 1997–2002 applications | 63D-W0078-01-00 |
| Yamaha | P40 | 40 | 2-Stroke | 1998 application listed | 63D-W0078-01-00 |
| Yamaha | C50 | 50 | 2-Stroke | Selected 1999–2001 applications | 63D-W0078-01-00 |
| Yamaha | P50 | 50 | 2-Stroke | 1995–1996 applications | 63D-W0078-01-00 |
| Yamaha | F40 2.6L | 40 | 4-Stroke | 1999 application listed | 63D-W0078-01-00 |
| Yamaha | F50 | 50 | 4-Stroke | Selected 1995–2003 applications | 63D-W0078-01-00 |
| Yamaha | F60 | 60 | 4-Stroke | Selected 2002–2003 applications | 63D-W0078-01-00 |
| Yamaha | Later F50/F60 variants | 50–60 | 4-Stroke | Some later catalog records use 63D-W0078-03-00; verify the exact model and year | 63D-W0078-03-00 |
Important: Do not rely on horsepower alone. Yamaha model suffixes, shaft configuration, production year, and serial-number range can affect water pump fitment.
Technical Specs
- Product Type
- Water pump impeller service kit with pump cover
- Application
- Selected Yamaha 40/50 HP 2-stroke and F40/F50/F60 4-stroke outboards
- Installation
- Direct replacement for the applicable water pump service components
- Product Status
- Aftermarket replacement, not OEM
- Quality Information
- ISO 9002-certified facility production according to the supplied product information
What’s in the Box
- 1 x Water pump insert cup, Yamaha reference 63D-44322-00-00
- 1 x Impeller, Yamaha reference 697-44352-00-00
- 1 x Water pump cover, Yamaha reference 63D-44312-00-00
- 1 x Wear plate, Yamaha reference 63D-44323-00-00
- 1 x O-ring, Yamaha reference 93210-59MG7-00
- 1 x Water pump gasket, Yamaha reference 63D-44316-00-00
- 1 x Bolt set containing 4 bolts, Yamaha reference 90119-08M15-00
- 4 x Bolt washers, Yamaha reference 90209-08M02-00
- 1 x Water seal, Yamaha reference 663-44366-00-00
- 1 x Impeller key, Yamaha reference 90280-03M03-00
This package includes the pump cover listed above. It does not establish inclusion of a complete water pump housing; compare the contents with your original assembly before ordering.
Installation Notes
- Disconnect the battery and allow the engine to cool completely before beginning work.
- Drain the lower-unit gear lubricant according to the manufacturer’s service procedure.
- Remove the propeller and unbolt the lower unit from the upper engine casing.
- Lower the gearcase carefully and disconnect the speedometer tube if equipped.
- Remove the old water pump cover and service components. Note the orientation of the original parts.
- Clean the pump mounting surfaces and inspect the driveshaft, water tube, keyway, and mating surfaces for wear or damage.
- Install the new gasket, wear plate, impeller key, impeller, insert cup, O-ring, water seal, and pump cover in the correct order.
- Rotate the driveshaft in the manufacturer-specified direction while fitting the impeller blades into the cover.
- Apply only the appropriate marine lubricant where specified and tighten the fasteners to the manufacturer’s torque specifications.
- Reinstall the lower unit, ensuring correct alignment of the water tube, shift shaft, and driveshaft.
- Refill the gearcase with the correct lubricant, reinstall the propeller, and test the cooling-water flow before normal operation.
Follow the service manual for your exact Yamaha model. Professional installation is recommended if you are not experienced with lower-unit or water-pump service.
Troubleshooting & FAQ
How do I know if my water pump impeller needs replacing?
Common signs include a weak or inconsistent tell-tale stream, rising engine temperature at idle or low speed, or an overheat alarm. Inspect the impeller and related cooling components whenever these symptoms occur.
What is the recommended replacement interval?
Inspect the impeller according to the maintenance schedule for your exact engine. Saltwater, sand, silt, extended storage, and heavy use can accelerate wear, so replacement intervals may need to be shortened.
Why is my engine still overheating after installation?
Check the impeller orientation, key installation, pump-cover seal, water-tube alignment, intake screens, thermostat, and cooling passages. Also confirm that the replacement kit matches the complete engine model and year.
Does this kit include the complete water pump housing?
The listed package includes a water pump cover and the other service components shown in the box contents. A complete pump housing is not listed as an included component.
How do I confirm fitment?
Match your engine’s complete model designation, year, and serial-number range with the compatibility information and compare the existing OEM reference. If any identification detail differs, confirm with a qualified marine-parts professional before ordering.
Is this an OEM Yamaha kit?
No. This is an aftermarket replacement kit intended to replace the applicable Yamaha water pump service components.
Shipping speed and cost
Typical transit is 5–15 days, and standard shipping is free where available. Expedited options, delivery estimates, and destination restrictions are shown at checkout.
Warranty and returns
The product is covered by a 1-year warranty against manufacturing defects under normal use. Returns are accepted within the standard return window when the item is unused and in its original condition; consult the applicable store policy for details.
Safety & Important Information
- Verify the full engine model, year, shaft configuration, and existing part number before purchase.
- Compare the supplied components with your original water pump assembly. Do not install a component that differs in size, shape, or configuration.
- This is an aftermarket replacement and is not manufactured by Yamaha.
- Use the appropriate service manual and torque specifications for your engine.
- Professional installation is recommended for safe and reliable operation.
About Sea Sierra
- Pro-Grade Standards — We supply marine parts designed for dependable service in real-world operating conditions.
- Fast Global Fulfillment — Standard delivery is available to most regions, with estimated transit times shown at checkout.
- Manufacturer-Direct Value — Practical aftermarket replacement parts with clear application and package information.
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