Water Pump Impeller with Key – Fits Yamaha 9.9/15 HP and Mercury Mariner 9.9/15 HP Outboards
Water Pump Impeller with Key – Fits Yamaha 9.9/15 HP and Mercury Mariner 9.9/15 HP Outboards is backordered and will ship as soon as it is back in stock.
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Water Pump Impeller with Key – Fits Yamaha 9.9/15 HP and Mercury Ma...
Water Pump Impeller with Key – Fits Yamaha 9.9/15 HP and Mercury Mariner 9.9/15 HP Outboards is backordered and will ship as soon as it is back in stock.
Product Details
This water pump impeller with key is an aftermarket replacement for selected Yamaha and Mercury Mariner outboard water pump applications. The impeller circulates cooling water through the engine to support proper operating temperature and cooling-system performance.
Company fitment information covers Yamaha 9.9 HP and 15 HP outboards from 1984 and later, including applicable 2-stroke models, as well as selected Yamaha F9.9, T9.9, and FT9.9 4-stroke models. It also covers selected 2-stroke Mercury Mariner 9.9C and 15C models. Always verify the exact engine model and the part number against your service manual before ordering.
- Water pump impeller supplied with one matching key.
- Installs in the outboard lower unit water pump.
- Six-blade impeller design.
- Aftermarket replacement part; not manufactured by Yamaha or Mercury.
Part Number References
The following manufacturer and aftermarket references are associated with this replacement impeller. Part-number matching should be confirmed with the exact engine model and service documentation.
| Brand | Reference | Reference Type |
|---|---|---|
| Yamaha | 682-44352-00 | OEM reference |
| Yamaha | 682-44352-01-00 | OEM reference |
| Yamaha | 682-44352-02-00 | OEM reference |
| Yamaha | 682-44352-03-00 | OEM reference |
| Yamaha | 682-44352-40 | OEM reference |
| Mercury | 47-84027M | OEM reference |
| Mercury | 47-84027T | OEM reference |
| Mercury | 47-96619M | OEM reference |
| Sierra | 18-3074 | Aftermarket reference |
| GLM | 89880 | Aftermarket reference |
| Mallory | 9-45605 | Aftermarket reference |
Engine & Model Compatibility
Compatibility depends on the complete engine model, year, stroke, and serial-number range. The applications below reflect the available product fitment information and should be verified before installation.
| Brand | Model or Application | Rated HP | Stroke | Year or Range | Relevant Reference |
|---|---|---|---|---|---|
| Yamaha | Selected 9.9 HP and 15 HP outboards | 9.9 / 15 | 2-Stroke | 1984 and later | 682-44352-00, 682-44352-01-00, 682-44352-02-00, 682-44352-03-00, 682-44352-40 |
| Yamaha | F9.9 | 9.9 | 4-Stroke | Verify exact model year | 682-44352 series |
| Yamaha | T9.9 | 9.9 | 4-Stroke | Verify exact model year | 682-44352 series |
| Yamaha | FT9.9 | 9.9 | 4-Stroke | Verify exact model year | 682-44352 series |
| Mercury Mariner | 9.9C and 15C | 9.9 / 15 | 2-Stroke | Verify exact model year and serial range | 47-84027M, 47-84027T, 47-96619M |
Technical Specifications
- Product Type
- Water pump impeller with key
- Application
- Outboard lower-unit water pump
- Number of Blades
- 6
- Outside Diameter
- 1.565 in (approximately 39.75 mm)
- Bore
- 0.500 in (approximately 12.70 mm)
- Thickness
- 0.865 in (approximately 21.97 mm)
- Key Size
- 0.105 in (approximately 2.67 mm)
- Included Key
- Yes; one matching key is supplied with the impeller
What's in the Box
- 1 x Water pump impeller
- 1 x Matching impeller key
Installation Notes
- Confirm the replacement impeller, key, dimensions, and reference number before disassembly.
- Disconnect the battery and place the outboard in neutral. Follow the manufacturer's service-manual safety procedure.
- Remove the lower unit according to the service manual and disconnect any speedometer tube or other attached line as required.
- Remove the water pump housing cover and retain the fasteners in their original locations.
- Remove the old impeller and key. Inspect the pump housing, wear plate, drive shaft, and keyway for damage or excessive wear.
- Clean debris and corrosion from the pump components. Do not reuse a damaged key or worn pump component.
- Install the supplied key and fit the new impeller onto the drive shaft. Position the blades in the correct direction for the engine's normal shaft rotation.
- Reinstall the pump housing and lower unit using the manufacturer's torque specifications and sealing requirements.
- Run the engine only with an adequate water supply, such as in the water or with an appropriate flushing device, and confirm a strong tell-tale stream before normal use.
Troubleshooting & FAQ
How do I confirm that this impeller fits my engine?
Check the complete engine model, year, stroke, and serial-number range in your service manual. Then compare the existing impeller and key with the listed dimensions and reference numbers. Do not rely on horsepower alone.
Does this product include the key?
Yes. The package includes one water pump impeller and one matching key.
Is this impeller for 2-stroke or 4-stroke engines?
Company fitment information includes selected Yamaha 2-stroke 9.9 HP and 15 HP applications, selected Yamaha F9.9, T9.9, and FT9.9 4-stroke applications, and selected 2-stroke Mercury Mariner 9.9C and 15C applications. Verify the exact model before ordering.
What are common signs of a worn impeller?
Typical signs include a weak or missing tell-tale stream, overheating, an overheating alarm, or visible cracking, hardening, or missing impeller blades.
Is this an OEM impeller?
No. This is an aftermarket replacement. Yamaha, Mercury, Mariner, Sierra, GLM, and Mallory names and numbers are provided only for application and reference purposes.
Should I replace other water-pump parts at the same time?
Inspect the pump housing, wear plate, gasket or seal, drive-shaft keyway, and related hardware during installation. Replace any component that is damaged or worn according to the engine manufacturer's service instructions.
Safety & Important Information
- Verify the exact engine model, year, stroke, and serial-number range before purchase.
- Compare the old impeller, key, dimensions, and reference number before installation.
- Never run an outboard without an adequate water supply.
- Professional installation is recommended if you are not familiar with lower-unit or water-pump service.
- This is an aftermarket replacement, not an OEM component.
About Sea Sierra
- Marine Replacement Parts — Practical aftermarket parts for common outboard maintenance and repair applications.
- Application-Focused Information — Reference numbers and fitment details are provided to support accurate part selection.
- Customer Support — Contact support if you need help comparing your existing impeller and engine information before ordering.
Payment & Security
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