Water Pump Repair Kit – Fits Yamaha F30, F40 (Replaces Yamaha 6BG-W0078-00-00, 6BG-W0078-01-00, Sierra 18-3490)
Water Pump Repair Kit – Fits Yamaha F30, F40 (Replaces Yamaha 6BG-W0078-00-00, 6BG-W0078-01-00, Sierra 18-3490) 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 – Fits Yamaha F30, F40 (Replaces Yamaha 6BG-W...
Water Pump Repair Kit – Fits Yamaha F30, F40 (Replaces Yamaha 6BG-W0078-00-00, 6BG-W0078-01-00, Sierra 18-3490) is backordered and will ship as soon as it is back in stock.
Product Details
This Water Pump Repair Kit – Fits Yamaha F30, F40 Outboard Motors contains all necessary components to restore your engine's cooling system. It is designed for Yamaha 30–40 HP 4-stroke models from 2008–2017, including F30, F40, and T25 High Thrust variants, ensuring reliable performance for a range of applications.
This kit is a direct replacement for Yamaha part numbers 6BG-W0078-00-00, 6BG-W0078-01-00, and Sierra 18-3490.
- Engineered for direct OEM-level fit and function.
- Restores cooling system performance to prevent overheating.
- Comprehensive kit includes impeller, housing, gaskets, and hardware.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket brands.
| Brand | Part Number |
|---|---|
| Yamaha | 6BG-W0078-00-00 |
| Yamaha | 6BG-W0078-01-00 |
| Sierra | 18-3490 |
Engine & Model Compatibility
Confirm your engine model and year in the table below to ensure accurate fitment.
This kit is designed for a wide range of Yamaha outboard motors.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Yamaha | F30 | 30 | 4-Stroke | 2013–2017 | 6BG-W0078-00-00 | |
| Yamaha | F30TLR | 30 | 4-Stroke | 2001–2005 | 6BG-W0078-00-00 | |
| Yamaha | F40 | 40 | 4-Stroke | 2008–2017 | 6BG-W0078-00-00 | |
| Yamaha | F40B | 40 | 4-Stroke | 2001–2008 | 6BG-W0078-00-00 | |
| Yamaha | F40EJR | 40 | 4-Stroke | 2003–2006 | 6BG-W0078-00-00 | |
| Yamaha | F40ESR | 40 | 4-Stroke | 2000–2003 | 6BG-W0078-00-00 | |
| Yamaha | F40MJH | 40 | 4-Stroke | 2002–2006 | 6BG-W0078-00-00 | |
| Yamaha | F40MLH | 40 | 4-Stroke | 2000–2006 | 6BG-W0078-00-00 | |
| Yamaha | F40MSH | 40 | 4-Stroke | 2000–2006 | 6BG-W0078-00-00 | |
| Yamaha | F40TLR | 40 | 4-Stroke | 2000–2006 | 6BG-W0078-00-00 | |
| Yamaha | T25 | 25 | 4-Stroke | 2001–2019 | 6BG-W0078-00-00 | |
| Yamaha | T25LA | 25 | 4-Stroke | 2009–2016 | 6BG-W0078-00-00 | |
| Yamaha | T25TLR | 25 | 4-Stroke | 2001–2006 | 6BG-W0078-00-00 |
Technical Specs
- Product Type
- Water Pump Repair Kit
- Installation
- Direct OEM replacement
- Other Technical Attributes
- Designed for marine outboard cooling system
What’s in the Box
- 1 x Pump Housing Cover (63D-44312-00-00)
- 1 x Water Pump Gasket (63D-44316-00-00)
- 1 x Insert Cartridge (63D-44322-00-00)
- 1 x Outer Plate, Cartridge (63D-44323-00-00/66T-44323-00-00)
- 1 x Damper, Water Seal 2 (663-44366-00-00)
- 1 x Impeller (6H4-44352-02-00)
- 4 x Bolt, With Washer (90119-08M15-00)
- 1 x Key, Woodruff (90280-03M03-00)
- 1 x O-Ring (93210-59MG7-00)
Installation Notes
- Disconnect the battery and shift linkage.
- Remove the lower unit (gearcase) mounting bolts.
- Carefully separate the lower unit from the upper casing.
- Unbolt and remove the old water pump housing.
- Note the orientation of the old impeller vanes before removing it and the woodruff key.
- Clean all mating surfaces of old gasket material and debris.
- Install the new woodruff key, O-rings, gaskets, and impeller (turn clockwise to seat vanes).
- Assemble the new housing components and torque bolts to manufacturer specifications.
- Reinstall the lower unit, ensuring the water tube and driveshaft are aligned.
- Reconnect the shift linkage and battery, then test the engine with a water supply.
Troubleshooting & FAQ
Which Yamaha models does this kit fit?
This kit is designed for a range of 25, 30, and 40 HP 4-stroke Yamaha outboards, including models like the F30, F40, and T25. Please review the detailed "Engine & Model Compatibility" table to confirm your specific model and year range before ordering.
What are the signs of a failing water pump impeller?
Common symptoms include a weak or intermittent water stream from the "telltale" outlet, engine overheating alerts, and, in severe cases, steam from the exhaust. A brittle, cracked, or deformed impeller upon inspection confirms the need for replacement.
How often should I replace my outboard's water pump kit?
As a general maintenance guideline, it's recommended to inspect the impeller annually and replace the entire water pump kit every 2-3 years or 200-300 hours of use, whichever comes first. This interval can be shorter if you operate frequently in sandy, silty, or saltwater conditions.
Does this kit replace both 6BG-W0078-00-00 and 6BG-W0078-01-00?
Yes, this kit is a direct aftermarket replacement for both Yamaha OEM part numbers 6BG-W0078-00-00 and its superseded version, 6BG-W0078-01-00.
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.
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.
