Water Pump Impeller Kit – Fits Yamaha 9.9/13.5/15/20HP 4-Stroke Outboards (Replaces 6AH-W0078-00)
Water Pump Impeller Kit – Fits Yamaha 9.9/13.5/15/20HP 4-Stroke Outboards (Replaces 6AH-W0078-00) 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 Impeller Kit – Fits Yamaha 9.9/13.5/15/20HP 4-Stroke Out...
Water Pump Impeller Kit – Fits Yamaha 9.9/13.5/15/20HP 4-Stroke Outboards (Replaces 6AH-W0078-00) is backordered and will ship as soon as it is back in stock.
Product Details
This aftermarket Water Pump Impeller Kit is engineered to fit Yamaha 4-Stroke outboard models including the F9.9, F13.5, F15C, and F20 series from approximately 2006 to 2023. It provides all the necessary components for a complete water pump overhaul to restore your engine's cooling performance.
It serves as a direct interchange for Yamaha OEM part numbers 6AH-W0078-00-00, 6AH-W0078-01-00, and 6AH-W0078-02-00.
- Designed for direct OEM-replacement installation.
- Features a durable cast iron water pump housing.
- Complete kit includes impeller, housing, plates, gaskets, and hardware.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number | Superseded By | Notes |
|---|---|---|---|
| Yamaha | 6AH-W0078-00-00 | 6AH-W0078-01-00 | |
| Yamaha | 6AH-W0078-01-00 | 6AH-W0078-02-00 | |
| Yamaha | 6AH-W0078-02-00 | Current Version |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
Fits a range of Yamaha 4-stroke outboard motors from 9.9HP to 20HP.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Yamaha | F9.9 | 9.9 | 4-Stroke | 2009–2016 | 6AH-W0078-00-00 | 6CA1-6AC9 |
| Yamaha | F13.5 | 13.5 | 4-Stroke | 2007–2009 | 6AH-W0078-00-00 | 6AF1-6AF3 |
| Yamaha | F15 | 15 | 4-Stroke | 2007–2014 | 6AH-W0078-00-00 | 6AG1-6AG9 |
| Yamaha | F15 | 15 | 4-Stroke | 2015–2016 | 6AH-W0078-00-00 | 6AGA-6AGB |
| Yamaha | F15C | 15 | 4-Stroke | 2008–2017 | 6AH-W0078-00-00 | F15CEHL, F15CEHS |
| Yamaha | F15C | 15 | 4-Stroke | 2007–2017 | 6AH-W0078-00-00 | F15CMHL, F15CMHS |
| Yamaha | F15L | 15 | 4-Stroke | 2007–2022 | 6AH-W0078-00-00 | F15LEHA, F15LMHA |
| Yamaha | F20 | 20 | 4-Stroke | 2007–2014 | 6AH-W0078-00-00 | 6AH1-6AH9 |
| Yamaha | F20 | 20 | 4-Stroke | 2015–2016 | 6AH-W0078-00-00 | 6AHA-6AHB |
| Yamaha | F20B | 20 | 4-Stroke | 2007–2017 | 6AH-W0078-00-00 | F20BEHPL, F20BEPL, F20BMHL, F20BMHS |
| Yamaha | F20L | 20 | 4-Stroke | 2007–2022 | 6AH-W0078-00-00 | F20LMHA, F20LPA, F20LPHA |
Technical Specs
- Product Type
- Water Pump Impeller Repair Kit
- Installation
- Direct OEM replacement
- Housing Material
- Cast Iron
What’s in the Box
- 1 x Water Pump Housing (6AH-44311-00-00)
- 1 x Cartridge Insert (63V-44322-00-00)
- 1 x Water Seal Damper (6L2-44367-00-00/6L2-44367-01-00)
- 1 x Impeller (63V-44352-01-00)
- 1 x Woodruff Key (664-44338-00-00)
- 1 x O-Ring (93210-49046-00)
- 1 x Cartridge Outer Plate (68T-44323-00-00)
- 2 x Dowel Pins (93604-10M03-00)
- 4 x Bolts (97095-08045-00)
- 2 x Plates (63V-44328-01-00)
Installation Notes
- Disconnect the negative battery cable before starting work.
- Place a drain pan under the lower unit and remove the gearcase oil drain screw to empty the oil.
- Remove the bolts securing the lower unit (gearcase) to the engine's upper casing and carefully lower it.
- Unbolt and remove the old water pump housing to access the impeller and other components.
- Clean all mating surfaces thoroughly, removing any old gasket material or sealant.
- Install the new woodruff key, impeller, plates, and gaskets as provided in the kit. Ensure the impeller blades are oriented in the direction of driveshaft rotation.
- Seat the new housing and tighten the bolts to the manufacturer's specified torque.
- Reinstall the lower unit, refill with fresh gearcase lubricant, and reconnect the battery.
- Start the engine in a suitable water source and verify a strong, steady stream from the cooling system's tell-tale outlet.
Troubleshooting & FAQ
How do I know if my water pump needs replacing?
Common signs include a weak or intermittent water stream from the tell-tale outlet, engine overheating alarms, or a visibly cracked, brittle, or deformed impeller discovered during a routine inspection.
What is the recommended replacement interval for this kit?
For preventative maintenance and to ensure engine reliability, we recommend inspecting the impeller annually and replacing the entire water pump kit every 2-3 years or 200-300 hours of operation, whichever comes first.
Will this fit my specific engine serial number?
This kit fits the models and years listed in the compatibility table. For certain models, the 'Notes' column provides additional serial number range details. Always cross-reference your engine's model and year against the table to ensure fitment.
What are the signs of an incorrectly installed impeller?
Immediate overheating, no water stream from the tell-tale, or an unusually weak stream are primary indicators. This can happen if the impeller blades are folded in the wrong direction or if the woodruff key was not installed correctly, preventing the impeller from spinning with the driveshaft.
OEM vs. Aftermarket: What's the difference?
This listing is an aftermarket replacement (not OEM). It is built to OEM-level specifications with comparable materials. All our parts are manufactured in an ISO 9002 facility and are batch-inspected for quality and consistency.
What are the shipping speed & costs?
We ship worldwide quickly—typical transit is 5–15 days. Standard shipping is free; expedited options will appear at checkout if available for your location.
What is the warranty and return policy?
This product is covered by a 1-year warranty against manufacturing defects under normal use. If you encounter any issues, please contact our support team with your order details. Returns are accepted within our standard window, provided the item is unused and in its 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 quality control.
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.
