Water Pump Service Kit with Housing for Yamaha T25, F30 and F40 4-Stroke Outboards, 2000–2009
Water Pump Service Kit with Housing for Yamaha T25, F30 and F40 4-Stroke Outboards, 2000–2009 is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
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Water Pump Service Kit with Housing for Yamaha T25, F30 and F40 4-S...
Water Pump Service Kit with Housing for Yamaha T25, F30 and F40 4-Stroke Outboards, 2000–2009 is backordered and will ship as soon as it is back in stock.
Product Details
This aftermarket water pump service kit with housing is designed for selected Yamaha T25, F30 and F40 4-stroke outboard engines from model years 2000–2009. It provides the main components needed to service the water pump and restore reliable cooling-system water circulation.
The kit is supplied with a water pump housing and is intended as a replacement for the Yamaha water pump assembly identified by OEM reference 66T-W0078-00. Related catalog references include Yamaha 66T-44311-00 and Sierra water pump kit references 18-3413 and 18-3440. Always compare the original pump, engine model and model year before ordering.
- Water pump service kit supplied with housing.
- For Yamaha T25, F30 and F40 4-stroke outboards within the stated year range.
- Includes the impeller, pump-service sealing components and related pump hardware listed below.
- Aftermarket replacement part; Yamaha and Sierra names and numbers are used only to identify application and reference compatibility.
Part Number Matrix
These are customer-facing manufacturer or aftermarket reference numbers associated with this water pump service application. They are provided for identification only and do not indicate that the product is manufactured by Yamaha or Sierra.
| Brand | Reference Number | Reference Type |
|---|---|---|
| Yamaha | 66T-W0078-00 | OEM water pump kit reference |
| Yamaha | 66T-44311-00 | OEM water pump housing reference |
| Sierra | 18-3413 | Aftermarket water pump kit reference |
| Sierra | 18-3440 | Aftermarket water pump kit reference |
Engine & Model Compatibility
Company fitment information identifies this service kit for Yamaha 4-stroke T25, F30 and F40 outboards from 2000 through 2009. Model suffixes, shaft lengths and regional configurations can affect fitment, so verify the complete model designation and the existing water pump before installation.
| Brand | Model Family | Rated HP | Stroke | Model Years | Primary OEM Reference |
|---|---|---|---|---|---|
| Yamaha | T25 | 25 HP | 4-Stroke | 2000–2009 | 66T-W0078-00 |
| Yamaha | F30 | 30 HP | 4-Stroke | 2000–2009 | 66T-W0078-00 |
| Yamaha | F40 | 40 HP | 4-Stroke | 2000–2009 | 66T-W0078-00 |
Technical Specs
- Product Type
- Water pump service kit with housing
- Application
- Yamaha T25, F30 and F40 4-stroke outboards
- Fitment Years
- 2000–2009
- Installation
- Replacement water pump service components; verify the existing assembly before installation
- Brand Status
- Aftermarket replacement, not an OEM Yamaha component
What's in the Box
The service-kit configuration includes the following pump-service components. Quantities are based on the catalog component listing for the with-housing application.
- 1 x Water pump housing
- 1 x Water pump impeller
- 1 x Water pump case gasket
- 1 x Wear plate
- 1 x Impeller key
- 1 x Insert cup
- 1 x Pump housing cover
- 1 x O-ring
- 1 x Water seal
- 4 x Bolts and 4 x bolt washers
Installation Notes
- Disconnect the battery and follow the safety procedures in the applicable Yamaha service manual.
- Remove the lower unit from the outboard.
- Remove the existing water pump components and inspect the driveshaft, keyway and mounting surfaces.
- Clean away old gasket material and debris before installing the replacement parts.
- Install the gasket, wear plate, insert cup, seal and other service components in the correct order.
- Fit the impeller with the key properly seated. Confirm the impeller-vane orientation and rotate the driveshaft as specified by the service manual.
- Install the supplied housing, cover, bolts and washers. Tighten all fasteners to the manufacturer's specified torque.
- Reinstall the lower unit, reconnect the battery and test the engine in an appropriate water supply.
- Confirm a strong tell-tale stream and check carefully for leaks or overheating before normal operation.
Troubleshooting & FAQ
How do I confirm that this kit fits my Yamaha outboard?
Confirm that your engine is a Yamaha T25, F30 or F40 4-stroke model from 2000–2009 and compare the existing water pump and OEM reference with the information above. Verify the complete model designation before purchase because suffixes and configurations can vary.
Does this kit include the water pump housing?
Yes. The company product description identifies this product as a water pump service kit with housing.
What are the signs of a worn water pump?
Common signs include a weak or missing tell-tale stream, overheating, a temperature warning, or visible damage to the impeller and pump housing. Stop operation if the engine overheats and inspect the cooling system.
Should all service-kit components be replaced together?
For a complete water pump service, replace the included wear, sealing and pump components as appropriate for the condition of the old assembly. Follow the engine manufacturer's service procedures and inspect the driveshaft and mating surfaces during installation.
Is this an OEM Yamaha kit?
No. This is an aftermarket replacement kit. Yamaha OEM numbers are included only as application and identification references.
How often should the water pump be serviced?
Service intervals depend on the engine manufacturer's schedule and operating conditions. Inspect the water pump regularly, especially after operation in saltwater, silty water or areas with heavy debris.
Safety & Important Information
- Verify the complete engine model, year and existing pump assembly before ordering.
- Do not operate the outboard without an adequate water supply for cooling.
- Use the applicable service manual for removal, installation and torque specifications.
- Professional installation is recommended if you are not familiar with lower-unit or water-pump service.
- This is an aftermarket replacement part and is not manufactured or endorsed by Yamaha.
About Sea Sierra
- Marine Replacement Parts — We provide aftermarket components for routine boat and outboard maintenance.
- Application-Focused Listings — Product descriptions identify the supported engine families and reference numbers to help with part selection.
- Service-Oriented Support — Compare your original component and engine identification information before installation for the best fit.
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