Water Pump Impeller Repair Kit – Fits Yamaha 8HP/9.9HP (Replaces 68T-W0078-00-00, 18-3450)
Water Pump Impeller Repair Kit – Fits Yamaha 8HP/9.9HP (Replaces 68T-W0078-00-00, 18-3450) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
Orders are typically processed within 1–2 business days.
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Water Pump Impeller Repair Kit – Fits Yamaha 8HP/9.9HP (Replaces 68...
Water Pump Impeller Repair Kit – Fits Yamaha 8HP/9.9HP (Replaces 68T-W0078-00-00, 18-3450) is backordered and will ship as soon as it is back in stock.
Product Details
This is a complete Water Pump Impeller Repair Kit – Fits Yamaha 8HP/9.9HP Outboards (Replaces 68T-W0078-00-00), designed for Yamaha 4-stroke 8HP and 9.9HP engines. The kit provides all the necessary components for a comprehensive water pump service, ensuring your engine maintains optimal cooling performance.
This kit serves as a direct replacement for Yamaha OEM part numbers 68T-W0078-00-00, 68T-W0078-01-00, and 68T-W0078-02-00, and also interchanges with Sierra 18-3450 and Mallory 9-48613.
- Engineered for direct OEM replacement fitment, simplifying installation.
- Features a durable impeller made from high-quality rubber designed to withstand extended saltwater immersion.
- Includes a full set of gaskets, plates, and hardware for a complete rebuild.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number | Notes |
|---|---|---|
| Yamaha | 68T-W0078-00-00 | Original part number. Superseded by 68T-W0078-01-00. |
| Yamaha | 68T-W0078-01-00 | Supersedes 68T-W0078-00-00. Is superseded by 68T-W0078-02-00. |
| Yamaha | 68T-W0078-02-00 | Current part number. Supersedes 68T-W0078-01-00. |
| Sierra | 18-3450 | Aftermarket interchange. |
| Mallory | 9-48613 | Aftermarket interchange. |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Yamaha | F6 | 6 HP | 4-Stroke | Up to 06/2008 | 68T-W0078-00-00 | Later models use 68T-W0078-02-00 |
| Yamaha | F8 | 8 HP | 4-Stroke | Up to 06/2008 | 68T-W0078-00-00 | Later models use 68T-W0078-02-00 |
| Yamaha | F9.9 | 9.9 HP | 4-Stroke | Up to 06/2008 | 68T-W0078-00-00 | Later models use 68T-W0078-02-00 |
Technical Specs
- Product Type
- Water Pump Repair Kit
- Installation
- Direct OEM replacement
- Impeller Material
- High quality rubber
- Technical Attributes
- Impellers manufactured to withstand extended salt water immersion
What’s in the Box
- 1 x Cartridge Insert (63V-44322-00-00)
- 1 x Water Seal Damper 2 (68T-44366-00-00)
- 1 x Impeller (68T-44352-00-00)
- 1 x Woodruff Key (664-44338-00-00)
- 1 x O-Ring (93210-44704-00)
- 1 x Cartridge Outer Plate (68T-44323-00-00)
- 4 x Bolts (97095-08045-00)
Installation Notes
- Disconnect the battery and shift linkage before starting.
- Unbolt and carefully lower the gearcase (lower unit) from the engine's midsection.
- Locate and unbolt the water pump housing cover to access the impeller.
- Remove the old impeller, key, gaskets, and plates. Note the rotational direction of the old impeller vanes.
- Thoroughly clean all mating surfaces, removing any old gasket material or corrosion.
- Install the new components from the kit in the reverse order of disassembly.
- Lightly grease the new impeller and insert it into the housing while turning the driveshaft in its normal rotational direction.
- Reassemble the pump housing, reinstall the lower unit, and reconnect all linkages. Once reassembled, test run the engine in water and confirm a steady stream from the tell-tale outlet.
Troubleshooting & FAQ
How do I know if this kit fits my Yamaha engine?
This kit is specifically designed for Yamaha F6, F8, and F9.9 4-stroke models manufactured up to June 2008. The best way to confirm fitment is to check your engine's original part number and compare it to the references in our Part Number Matrix.
What are the signs of a failing water pump impeller?
Common signs of a worn or damaged impeller include the engine overheating at idle or low speeds, a weak or intermittent water stream from the "tell-tale" outlet, or an audible alarm from the engine's warning system.
How often should the water pump impeller be replaced?
As a crucial part of preventative maintenance, it is recommended to inspect and likely replace the impeller every one to two years, or every 100-200 hours of operation. Service intervals should be shorter for engines used frequently in saltwater or silty/sandy conditions.
What is the difference between the listed Yamaha part numbers?
The numbers 68T-W0078-00-00, 68T-W0078-01-00, and 68T-W0078-02-00 represent a supersession chain where Yamaha updated the part over time. Our aftermarket kit is designed to be a functional replacement for all of these OEM versions.
Is this a genuine OEM part or an aftermarket replacement?
This listing is for a high-quality aftermarket replacement, not an OEM part. It is built to meet or exceed OEM-level specifications with comparable materials and performance. Our parts are manufactured in an ISO 9002 certified facility and are batch-inspected for quality and consistency.
How fast is shipping and what does it cost?
We ship worldwide quickly, with typical transit times of 5–15 days for most regions. Standard shipping is free for all orders. Expedited shipping options and exact costs will be displayed 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 operating conditions. If you encounter any issues, please contact our support team with your order details. Returns are accepted within our standard return window for items that are unused and in their original packaging. Please see our full policy page or contact us 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.
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