Water Pump Repair Kit Without Housing for Yamaha 50–70 HP Outboards – Replaces 6H3-W0078-A0-00 and 6H3-W0078-02-00
Water Pump Repair Kit Without Housing for Yamaha 50–70 HP Outboards – Replaces 6H3-W0078-A0-00 and 6H3-W0078-02-00 is backordered and will ship as soon as it is back in stock.
Worry-free returns
Worry-free returns
Shop with confidence. If you’re not completely satisfied, eligible items may be returned within the return window, provided they are unused and in original packaging.
If the return is due to our error or a defective item, we’ll make it right.
Please contact us before returning any item.
Delivery and Shipping
Delivery and Shipping
Orders are typically processed within 1–2 business days.
U.S. orders usually arrive within 6–15 days, depending on stock location and destination.
International delivery times may vary due to customs processing.
Tracking information will be provided once your order ships.
Water Pump Repair Kit Without Housing for Yamaha 50–70 HP Outboards...
Water Pump Repair Kit Without Housing for Yamaha 50–70 HP Outboards – Replaces 6H3-W0078-A0-00 and 6H3-W0078-02-00 is backordered and will ship as soon as it is back in stock.
Product Details
This aftermarket water pump repair kit without housing is designed for selected Yamaha outboard water pump applications. It services the lower-unit cooling system and includes the impeller, insert cartridge, wear plate, gaskets, O-ring, key, and replacement bolts required for a water pump rebuild.
The kit is intended for selected Yamaha 2-stroke 60–70 HP models and Yamaha 4-stroke 50–60 HP models, including High Thrust applications. Always compare the water pump arrangement and original part numbers before ordering.
- Installation location: Lower unit / gearcase water pump
- Product type: Water pump repair kit without water pump housing
- Service function: Restores water-pump components used to circulate cooling water through the outboard
- Housing: Not included
Part Number References
The following manufacturer and aftermarket references are associated with this water pump repair-kit application. Part-number references do not replace model, year, stroke, and serial-number verification.
| Brand | Reference | Reference type |
|---|---|---|
| Yamaha | 6H3-W0078-A0-00 | OEM reference |
| Yamaha | 6H3-W0078-02-00 | OEM reference |
| Yamaha | 6H3-W0078-01-00 | Related OEM revision reference |
| Yamaha | 6H3-W0078-00-00 | Related OEM revision reference |
| Sierra | 18-3428-1 | Aftermarket catalog reference for the 6H3-W0078-00-00 / 6H3-W0078-A0-00 application |
| Sierra | 18-3466 | Aftermarket catalog reference associated with the 6H3-W0078-02-00 application |
| Sierra | 18-3461 | Related 6H3 water-pump kit reference; verify housing configuration before ordering |
Engine & Model Compatibility
The compatibility information below is limited to the applications represented by the supplied product data and catalog references. Yamaha model suffixes, production years, shaft lengths, and serial-number ranges must remain together when verifying fitment.
Yamaha 2-Stroke Applications
| Model family | Rated HP | Stroke | Years shown | Notes |
|---|---|---|---|---|
| 60F / 60TLR | 60 | 2-Stroke | 1997–2003 | Includes listed 60TLR suffixes such as 60TLRV, 60TLRA, and 60TLRB where applicable. |
| 70B / 70TLR | 70 | 2-Stroke | 1997–2003 | Includes listed 70TLR suffixes such as 70TLRV through 70TLRB where applicable. |
| C60TLR | 60 | 2-Stroke | 1997–2001 | Includes listed C60TLRV through C60TLRZ models. |
| C70TLR | 70 | 2-Stroke | 2000–2001 | Includes listed C70TLRY and C70TLRZ models. |
| P60TLH | 60 | 2-Stroke | 1997–1999 | Includes listed P60TLHV through P60TLHX models. |
Yamaha 4-Stroke Applications
| Model family | Rated HP | Stroke | Years shown | Notes |
|---|---|---|---|---|
| T50 / FT50 | 50 | 4-Stroke High Thrust | 1997–2003 | Verify the exact T50 or FT50 model suffix and serial range. |
| F50TLH / F50TLR | 50 | 4-Stroke | 1997 | Includes the listed F50TLHV and F50TLRV configurations. |
| T60 / FT60 | 60 | 4-Stroke High Thrust | 2003 | Verify the exact T60 or FT60 model suffix and serial range. |
Important: The catalog evidence also contains additional Yamaha model occurrences for related revisions. Those occurrences should not be treated as automatic confirmation for every model, year, stroke, shaft, or serial-number combination. Confirm the exact original water-pump assembly before installation.
Technical Specifications
- Product type
- Aftermarket water pump repair kit without housing
- Installation location
- Lower unit / gearcase
- Included housing
- No
- Primary application range
- Selected Yamaha 2-stroke 60–70 HP and 4-stroke 50–60 HP outboards
- Manufacturer status
- Aftermarket replacement; not a Yamaha-manufactured component
What's in the Box
- 1 × Cartridge insert / impeller cup — 663-44322-00-00
- 1 × Water pump impeller — 697-44352-00-00 / 6H3-44352-01 reference
- 1 × Water pump gasket — 6H3-44315-A0-00
- 1 × Cartridge outer plate / wear plate — 6H3-44323-00-00
- 1 × Cartridge gasket — 6H3-44324-A0-00
- 1 × Water pump gasket — 688-44316-A0-00
- 1 × O-ring — 93210-46044-00
- 2 × Bolts — 97095-08045-00
- 2 × Bolts — 97395-08055-00
- 1 × Woodruff key — 90280-03M03-00
The water pump housing is not included. Component part numbers are supplied as identification references; confirm the parts against the original assembly before disassembly.
Installation Notes
- Disconnect the battery and place the outboard in neutral.
- Remove the lower unit according to the engine manufacturer's service procedure.
- Secure the gearcase on a stable work surface.
- Remove the water pump cover and existing pump components.
- Clean the mating surfaces and inspect the housing, shaft, keyway, and wear surfaces for damage or corrosion.
- Install the supplied gaskets, insert cartridge, wear plate, impeller, O-ring, bolts, and Woodruff key in the correct order for the engine model.
- Use a suitable marine lubricant during impeller installation and rotate the driveshaft in the correct direction while seating the impeller in the housing.
- Tighten fasteners to the engine manufacturer's specified torque; do not substitute a generic torque value.
- Reinstall the lower unit and reconnect all linkages and other connections.
- Run the engine only with an adequate water supply, such as a test tank or approved flushing attachment, and verify a normal cooling-water telltale and operating temperature.
Troubleshooting & FAQ
What are common signs of a worn water pump?
A weak or absent telltale stream, overheating warning, rising operating temperature, or damaged and missing impeller vanes can indicate that the water pump requires inspection or service.
Does this kit include the water pump housing?
No. This listing is for a repair kit without the water pump housing. Inspect the existing housing and replace it separately if it is scored, distorted, cracked, or excessively worn.
Will this kit fit every Yamaha 50–70 HP outboard?
No. Fitment depends on the exact model, year, stroke, shaft configuration, and serial-number range. Verify the original water-pump part numbers and housing configuration before ordering.
Can the kit be installed without professional help?
Installation requires lower-unit removal, correct gasket placement, impeller-key alignment, and proper fastener torque. It may be completed by an experienced technician with the correct service information, but professional installation is recommended when in doubt.
Is this an OEM Yamaha part?
No. This is an aftermarket replacement kit. Yamaha and the listed manufacturer part numbers are used only to identify the application and replacement references.
How often should the impeller be serviced?
Inspect the impeller according to the engine manufacturer's maintenance schedule. Service intervals may need to be shorter in saltwater, sandy, silty, or heavily used conditions.
Safety & Important Information
- Confirm the complete model designation, year, stroke, shaft configuration, and serial-number range before purchase.
- Compare the original pump components and housing configuration with the supplied parts.
- Do not operate the outboard without an adequate cooling-water supply.
- Stop operation immediately if the engine overheats or the telltale stream is abnormal.
- This is an aftermarket replacement kit and does not include the water pump housing.
About Sea Sierra
Sea Sierra supplies aftermarket marine replacement parts for repair and maintenance applications. Product identification should always be confirmed against the original component and the manufacturer's service information before installation.
Payment & Security
Payment methods
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
