Aftermarket Water Pump Repair Kit Without Housing for Yamaha C40 and CV40 40 HP 2-Stroke Outboards (1990–1997) – Replaces 679-W0078-A1-00 and 6F5-W0078-A0-00
Aftermarket Water Pump Repair Kit Without Housing for Yamaha C40 and CV40 40 HP 2-Stroke Outboards (1990–1997) – Replaces 679-W0078-A1-00 and 6F5-W0078-A0-00 is backordered and will ship as soon as it is back in stock.
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Aftermarket Water Pump Repair Kit Without Housing for Yamaha C40 an...
Aftermarket Water Pump Repair Kit Without Housing for Yamaha C40 and CV40 40 HP 2-Stroke Outboards (1990–1997) – Replaces 679-W0078-A1-00 and 6F5-W0078-A0-00 is backordered and will ship as soon as it is back in stock.
Product Details
This aftermarket water pump repair kit is designed for Yamaha C40 and CV40 40 HP 2-stroke outboard motors. It is supplied without the water pump housing and is intended to service the existing pump assembly with replacement sealing, wear, drive, and impeller components.
The kit is listed for Yamaha CV40 models from 1990 and Yamaha C40 models from 1991–1997. It replaces Yamaha reference numbers 679-W0078-A1-00 and 6F5-W0078-A0-00. Confirm the exact engine model and year before ordering.
- Aftermarket water pump service kit supplied without the pump housing.
- Designed for Yamaha C40 and CV40 40 HP 2-stroke outboards within the listed application range.
- Includes an impeller, gaskets, seals, plates, key, fasteners, and related service components listed below.
- Use the existing water pump housing if it is serviceable and compatible with the engine.
Part Number Matrix
Use these manufacturer and aftermarket references when comparing the replacement kit with your existing water pump service parts.
| Reference Type | Part Number |
|---|---|
| Yamaha reference | 679-W0078-A1-00 |
| Yamaha reference | 6F5-W0078-A0-00 |
| Aftermarket reference | 18-3397 |
Engine & Model Compatibility
This kit is intended for the following Yamaha 2-stroke applications. Model, horsepower, stroke, and year conditions should be checked together.
| Brand | Model | Rated HP | Stroke | Applicable Year | Reference Numbers | Housing |
|---|---|---|---|---|---|---|
| Yamaha | CV40 | 40 | 2-Stroke | 1990 | 679-W0078-A1-00 / 6F5-W0078-A0-00 | Without housing |
| Yamaha | C40 | 40 | 2-Stroke | 1991–1997 | 679-W0078-A1-00 / 6F5-W0078-A0-00 | Without housing |
Technical Specs
- Product Type
- Water Pump Repair Kit
- Configuration
- Service kit without water pump housing
- Application
- Yamaha C40 and CV40 40 HP 2-stroke outboards
- Installation
- Replacement service components for the existing compatible water pump assembly
- Impeller Material
- Neoprene rubber
- Aftermarket Reference
- 18-3397
What’s in the Box
- 1 x Water Seal Damper 2 (663-44366-00-00)
- 1 x Cartridge Insert (676-44322-00-00)
- 1 x Water Pump Impeller (6F5-44352-00-00)
- 1 x Water Pump Gasket (676-44315-A1-00)
- 1 x Cartridge Outer Plate (676-44323-00-00)
- 1 x Cartridge Gasket (676-44324-A1-00)
- 1 x Water Pump Gasket (679-44316-A0-00)
- 2 x Bolts (97095-08055-00)
- 2 x Bolts (97095-08045-00)
- 4 x Washers (92990-08600-00)
- 1 x Woodruff Key (90280-04M00-00)
Important: The kit is supplied without the water pump housing. The existing housing must be reused only if it is compatible, undamaged, and within serviceable condition.
Installation Notes
- Place the outboard in a stable service position, disconnect the battery if applicable, and shift into neutral. Remove the lower unit according to the engine service procedure.
- Remove the existing water pump housing from the driveshaft. This product does not include a replacement housing.
- Remove the old impeller, woodruff key, plates, gaskets, seals, and related service parts. Note the orientation of each component before removal.
- Clean the mating surfaces of the existing pump housing and pump base. Remove old gasket material, corrosion, and debris without damaging the sealing surfaces.
- Inspect the existing housing, pump base, driveshaft, and keyway. Replace any damaged component before installing the service kit.
- Install the new water seal damper, cartridge insert, gaskets, plates, and other service components in the correct order for the engine.
- Install the new woodruff key in the driveshaft keyway.
- Apply a light coat of marine grease or a soap-and-water solution to the new impeller. Slide it over the key and rotate it in the correct direction so the vanes are not damaged.
- Fit the existing compatible housing over the impeller and driveshaft. Install the supplied fasteners and tighten them according to the engine manufacturer’s service specifications.
- Reinstall the lower unit and test the engine in water. Confirm a strong, steady cooling-water tell-tale stream before normal operation.
Troubleshooting & FAQ
Which engines does this water pump repair kit fit?
The company application specifies Yamaha CV40 40 HP 2-stroke models from 1990 and Yamaha C40 40 HP 2-stroke models from 1991–1997. Verify the exact model and year on your engine before ordering.
Does the kit include the water pump housing?
No. This is a service kit supplied without the water pump housing. You must reuse a compatible existing housing or obtain a housing separately.
What reference numbers does this kit replace?
The listed Yamaha reference numbers are 679-W0078-A1-00 and 6F5-W0078-A0-00. The aftermarket reference associated with the kit is 18-3397.
Can I install only the impeller?
The kit is intended to service the water pump as a set. Replace the included gaskets, seals, key, plates, and other service components as needed for a complete repair rather than automatically reusing worn or compressed sealing parts.
How do I know if the existing housing can be reused?
Inspect it for scoring, cracks, corrosion, distortion, and damage around the sealing and impeller surfaces. Do not reuse a housing that cannot provide a smooth, properly sealed pump assembly.
When should the impeller be replaced?
Inspect the impeller during scheduled maintenance and whenever the cooling-water stream is weak or intermittent, the engine overheats, or the pump has been exposed to abrasive sand or silt. Follow the engine manufacturer’s maintenance schedule where available.
Is this an OEM part?
No. This is an aftermarket replacement service kit designed for the listed Yamaha applications. Yamaha reference numbers are provided for identification and cross-reference only.
Safety & Important Info
- Confirm the complete engine model, horsepower, stroke, and year range before purchase.
- Confirm that your existing water pump housing is compatible and serviceable; the housing is not included.
- Do not operate the engine without an adequate cooling-water supply.
- Follow the engine service manual for lower-unit removal, installation sequence, fastener torque, and testing procedures.
- Professional installation is recommended if you are not experienced with outboard lower-unit or water-pump service.
About Sea Sierra
- Marine Replacement Parts — Practical aftermarket components for routine service and repair.
- Application-Focused Listings — Product references and fitment conditions are provided to help you compare your engine before ordering.
- Service Support — Review the listed model, year, stroke, and included components carefully before installation.
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