Water Pump Impeller Repair Kit with Housing – Fits Select Yamaha 40–60 HP 2-Stroke and 4-Stroke Outboards
Water Pump Impeller Repair Kit with Housing – Fits Select Yamaha 40–60 HP 2-Stroke and 4-Stroke Outboards is backordered and will ship as soon as it is back in stock.
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Water Pump Impeller Repair Kit with Housing – Fits Select Yamaha 40...
Water Pump Impeller Repair Kit with Housing – Fits Select Yamaha 40–60 HP 2-Stroke and 4-Stroke Outboards is backordered and will ship as soon as it is back in stock.
Product Details
This complete water pump impeller repair kit with housing components is designed for routine lower-unit water pump service on select Yamaha 40, 50, and 60 HP outboard engines. The kit replaces worn impeller and pump-service components to help restore proper cooling-water circulation.
Catalog references associate this repair-kit style with Yamaha water pump references including 63D-W0078-00, 63D-W0078-01, and related suffix variations. Aftermarket cross-references include Sierra 18-3415 and 18-3434, plus GLM 12276. These numbers are reference points only; always match the complete engine model, year, stroke, and existing pump components before ordering.
- Installs in the lower unit or gearcase water pump assembly.
- Includes the impeller, housing cover, cartridge components, gaskets, seal damper, key, and replacement bolts listed below.
- Aftermarket replacement part; not manufactured or supplied by Yamaha.
Part Number Matrix
The following are published OEM and aftermarket reference numbers associated with this repair-kit family. A number appearing in the same catalog family does not by itself confirm fitment for every engine listed.
| Brand | Reference Number | Reference Type |
|---|---|---|
| Yamaha | 63D-W0078-00 | OEM reference |
| Yamaha | 63D-W0078-01 | OEM reference |
| Yamaha | 63D-W0078-00-00 | OEM reference format |
| Yamaha | 63D-W0078-01-00 | OEM reference format |
| Yamaha | 63D-W0078-02-00 | Catalog cross-reference |
| Yamaha | 63D-W0078-03-00 | Catalog cross-reference |
| Yamaha | 6H4-W0078-00 | OEM reference |
| Yamaha | 6H4-W0078-01-00 | OEM reference format |
| Yamaha | 6H4-W0078-A0-00 | OEM reference format |
| Sierra | 18-3415 | Aftermarket cross-reference |
| Sierra | 18-3434 | Aftermarket cross-reference |
| GLM | 12276 | Aftermarket cross-reference |
Engine & Model Compatibility
Fitment depends on the complete Yamaha model designation and production year. The references below identify documented application groups, not a guarantee that every engine within a horsepower range uses the same pump assembly.
| Brand | Application Group | Rated HP | Stroke | Documented Reference | Fitment Guidance |
|---|---|---|---|---|---|
| Yamaha | Selected 40-series models, including 40EJRV, 40ELRV, 40ESRV, 40MJHV, 40MLHV, 40MSHV, 40TLHV, 40TLRV and C40TLRV families | 40 | 2-Stroke | 63D-W0078-01-00 | Model and year must be matched exactly. |
| Yamaha | Selected 50-series models, including 50EJRV, 50ELRV, 50TLHV and 50TLRV families | 50 | 2-Stroke | 63D-W0078-01-00 | Model and year must be matched exactly. |
| Yamaha | Selected 40- and 50-series earlier models | 40–50 | 2-Stroke | 63D-W0078-00-00 | Catalog applications include selected 1995–1996 models; verify the original pump assembly. |
| Yamaha | Selected F50LB, F50LB2, F60JB and F60LB applications | 50–60 | 4-Stroke | 63D-W0078-03-00 | Catalog records document later model-year applications; verify the exact year and model suffix. |
| Yamaha | Selected F40, F50 and F60 applications using the 63D/related pump family | 40–60 | 4-Stroke | 63D-W0078 series | Do not rely on horsepower alone; compare the full model number and pump components. |
Technical Specifications
- Product Type
- Water pump impeller repair kit with housing components
- Installation Location
- Lower unit / gearcase water pump assembly
- Application Range
- Select Yamaha 40–60 HP 2-stroke and 4-stroke outboards
- Product Status
- Aftermarket replacement; not an OEM Yamaha component
What's in the Box
- 1 x Cartridge Insert (63D-44322-00-00)
- 1 x Water Pump 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)
Component part numbers are included for identification and service-reference purposes. Confirm the physical configuration of the existing pump before installation.
Installation Notes
- Disconnect the battery and spark-plug leads, place the outboard in neutral, and secure the boat before beginning service.
- Support the lower unit and remove the gearcase according to the service manual for your specific engine.
- Remove the water-pump housing and note the orientation of the old impeller, key, plate, gaskets, and seals.
- Clean the driveshaft, pump cavity, housing surfaces, and water passages. Remove all gasket residue.
- Install the gasket, cartridge or wear components, Woodruff key, impeller, seal, and housing in the correct order for your pump design.
- Turn the driveshaft in the specified direction while installing the housing so the impeller vanes seat correctly. Do not force the housing over the vanes.
- Install the supplied bolts and washers and tighten them to the torque specification in the engine service manual.
- Reinstall the lower unit, reconnect all linkages and electrical connections, refill gearcase oil as required, and test the cooling-water tell-tale before operating the engine.
Troubleshooting & FAQ
How do I confirm this kit fits my engine?
Match the complete model designation, production year, stroke type, and existing water-pump reference. For example, a horsepower-only match is not sufficient because Yamaha used different pump configurations within similar horsepower ranges.
What are signs of a worn water-pump impeller?
Common symptoms include overheating, a weak or intermittent tell-tale stream, reduced cooling-water flow at idle, or visible damage to the impeller vanes. Stop operation if the engine overheats.
Does the kit include the housing?
Yes. This listing includes the water-pump housing cover and the cartridge, plate, impeller, gasket, seal, key, and hardware listed in the package-contents section.
Can I install the kit myself?
This service requires mechanical experience and model-specific tools. Follow the service manual for the exact engine and use the manufacturer's torque specifications. If you are unsure, have a qualified marine technician perform the work.
Is this an OEM Yamaha part?
No. This is an aftermarket replacement kit. Yamaha, Sierra, and GLM names and part numbers are used only to identify compatible reference applications.
Safety & Important Information
- Verify the full engine model, year, stroke, serial-number range where applicable, and original pump configuration before ordering.
- Do not operate an outboard without an adequate water supply. Test the cooling-water stream before placing the engine under load.
- Improper impeller orientation, missing gaskets, incorrect torque, or blocked water passages can cause overheating and severe engine damage.
- This is an aftermarket replacement part, not an OEM component. Reference numbers are provided for comparison only.
About Sea Sierra
- Marine Maintenance Parts — Replacement components for routine outboard and lower-unit service.
- Reference-Based Fitment — Product information is organized around OEM and aftermarket reference numbers to help customers compare their original parts.
- Service-Focused Support — When fitment is uncertain, provide the complete engine model and year before ordering.
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