Water Pump Repair Kit – Fits Yamaha 25HP/30HP 2-Stroke (Replaces 689-W0078-A6-00)
Water Pump Repair Kit – Fits Yamaha 25HP/30HP 2-Stroke (Replaces 689-W0078-A6-00) is backordered and will ship as soon as it is back in stock.
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Worry-free returns
Worry-free returns
You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).
You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).
If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.
Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Product Details
This Water Pump Repair Kit – Fits Yamaha 25HP/30HP 2-Stroke (Replaces 689-W0078-A6-00) provides all necessary components for a complete water pump overhaul. It is specifically designed to fit Yamaha 25HP (C25) and 30HP (C30) 2-Stroke outboard models manufactured between 1990 and 1997.
This kit serves as a direct aftermarket replacement for Yamaha part numbers 689-W0078-A6-00, 689-W0078-06-00, and 689-W0078-05-00, along with interchange references for Sierra 18-3427 and GLM 12014.
- Engineered for direct-mount installation on the lower unit.
- Restores cooling system performance for marine environments.
- Includes the essential impeller, housing, gaskets, and hardware for a full replacement.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Yamaha | 689-W0078-A6-00 |
| Yamaha | 689-W0078-06-00 |
| Yamaha | 689-W0078-05-00 |
| Sierra | 18-3427 |
| GLM | 12014 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For Yamaha engines, verify that your model code (e.g., C25) and production year fall within the specified range for a guaranteed fit.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Yamaha | C25 | 25 | 2-Stroke | 1990–1997 | 689-W0078-A6-00 | |
| Yamaha | C30 | 30 | 2-Stroke | 1990–1992 | 689-W0078-A6-00 |
Technical Specs
- Product Type
- Water Pump Repair Kit
- Installation
- Direct replacement
- Fuel Type
- Gasoline
- Connection
- Direct mount to lower unit
- Housing Material
- Aluminum/Plastic composite
- Housing Color
- Silver/Black
- Dimensions
- 18.0" L x 14.0" W x 7.0" H
- Fitting Type
- OEM replacement
- Application
- For marine cooling system maintenance
What’s in the Box
- 1 x Water Seal Damper 1 (626-44365-01-00)
- 1 x Water Pump Housing (689-44311-03-00)
- 3 x Bolts, With Washers (90119-06M07-00)
- 1 x Cartridge Insert (689-W4432-02-00)
- 1 x Cartridge Outer Plate (689-44323-03-00)
- 1 x Cartridge Gasket (689-44324-A0-00)
- 1 x Impeller (689-44352-02-00)
- 1 x Water Pump Gasket (689-44316-A0-00)
- 1 x Woodruff Key (664-44338-00-00)
Installation Notes
- Disconnect the battery and spark plug wires for safety.
- Place the outboard in neutral and drain the gearcase oil from the lower unit.
- Remove the bolts securing the lower unit (gearcase) to the mid-section and carefully lower it.
- Unbolt and remove the old water pump housing to access the impeller and wear plates.
- Clean all mating surfaces thoroughly, removing any old gasket material or sealant.
- Install the new woodruff key, impeller, gaskets, and plates as provided in the kit. Ensure the impeller vanes are oriented correctly.
- Secure the new water pump housing with the provided bolts, tightening them to the manufacturer's specified torque.
- Carefully reinstall the lower unit, ensuring the driveshaft, shift rod, and water tube are properly aligned.
- Refill the gearcase with fresh marine gear lube.
- Reconnect the battery and test the engine in a suitable water source, confirming a strong, steady stream from the tell-tale outlet.
Troubleshooting & FAQ
How do I know if this kit fits my engine?
This kit fits specific Yamaha 25HP (C25) and 30HP (C30) 2-Stroke models. To ensure compatibility, you must verify your engine's model, horsepower, and production year against our "Engine & Model Compatibility" table before purchase.
What are the signs of a failing water pump?
Common symptoms include the engine overheating at idle or low speeds, a weak or intermittent water stream from the tell-tale outlet, and a brittle or cracked impeller found during inspection.
How often should I replace my water pump impeller?
As a crucial part of preventative maintenance, we recommend replacing the impeller every 1-2 years or every 100-200 hours of use. More frequent changes are advised if you operate primarily in saltwater or silty/sandy conditions.
Is this a complete kit for the job?
Yes, this is a comprehensive repair kit that includes the impeller, housing, wear plates, gaskets, seals, and necessary hardware for a full assembly replacement. Please see the "What’s in the Box" list for all included items.
Can I just replace the impeller instead of the whole kit?
While technically possible, it is strongly recommended to replace the entire assembly. The housing, wear plates, and seals degrade over time and can cause a new impeller to perform inefficiently or fail prematurely.
What's the difference between OEM and this aftermarket part?
This listing is for a high-quality aftermarket replacement part, not an original equipment manufacturer (OEM) component. It is built to meet or exceed OEM-level specifications using comparable materials and is manufactured in an ISO 9002 certified facility, with batch inspections to ensure quality and consistency.
How much is shipping and how long does it take?
We offer fast worldwide shipping, with a typical transit time of 5–15 days for most regions. Standard shipping is free on all orders. If available for your location, expedited shipping options and their costs will be presented at checkout.
What is the warranty and return policy?
This product is covered by a 1-year warranty against manufacturing defects under normal marine use. If you encounter an issue, please contact our support team with your order details. Returns are accepted within our standard window for items that are unused and in their 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
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