Water Pump Impeller Kit – Fits Yamaha 6/8 HP Outboards (Replaces 6N0-W0078-A0-00, 6G1-W0078-A1-00)

This water pump impeller service kit provides a complete solution for maintaining the cooling system on select Yamaha 2-Stroke outboards. It is designed for Yamaha 6–8 HP models (1996 and newer), including the 6C, 6D, 6J, 8C, 8J, and 8N series engines.

As a direct replacement for multiple OEM part numbers, this kit ensures compatibility and restores performance, preventing engine overheating by maintaining proper water circulation.

• Includes a complete set of components for a full service: impeller, gaskets, plates, and hardware.
• Engineered for a direct fit in the lower unit for straightforward installation.
• Features a durable, high-quality neoprene impeller for reliable operation in marine environments.

Use this table to confirm equivalent part numbers across OEM and aftermarket brands.

Confirm your engine model/year in the table below. For Yamaha owners, here’s a guide to help you identify your engine’s serial/model: Yamaha Serial Number Guide. You can also review exploded diagrams to verify part numbers: Yamaha Parts Diagrams & Catalog.

• 1 x Water Pump Gasket (6G1-44315-A0-00)
• 1 x Cartridge Insert (6G1-44322-00-00)
• 1 x Cartridge Outer Plate (6G1-44323-00-00)
• 1 x Water Seal Damper 2 (647-44366-00-00)
• 1 x Impeller (6G1-44352-00-00)
• 2 x Plates (6G1-44328-00-00)
• 4 x Bolts (97080-06045-00)

1. Safety First: Disconnect the battery and shift the outboard into the neutral position.
2. Access the Pump: Remove the lower unit mounting bolts and carefully drop the lower unit to access the water pump assembly.
3. Disassemble Housing: Unbolt and remove the water pump housing cover to expose the old impeller.
4. Remove Old Components: Take out the old impeller, gaskets, and wear plates, paying close attention to their original orientation.
5. Clean Surfaces: Thoroughly clean any old gasket material or debris from the housing surfaces to ensure a proper seal.
6. Install New Parts: Install the new gaskets, wear plate, and cartridge insert from the kit.
7. Install Impeller: Slide the new impeller onto the driveshaft. Rotate the shaft clockwise while pushing down to correctly orient the impeller vanes.
8. Reassemble: Re-install the outer plate, water seal damper, and housing. Tighten the housing bolts to the manufacturer’s specified torque.
9. Final Assembly: Reattach the lower unit to the upper casing and secure it with the mounting bolts.
10. Test Operation: Reconnect the battery, supply the engine with water using flushing muffs, and run it to verify a strong, consistent water stream from the tell-tale outlet.

How do I confirm this kit fits my Yamaha engine?
This kit is designed for Yamaha 6 HP and 8 HP 2-stroke outboards manufactured from 1996 onward, including 6C, 6D, 8C, and 8J series. To ensure a perfect match, find your specific model and year in our "Compatible Engine Models" table. You can also cross-reference your current part number with those listed, such as Yamaha 6N0-W0078-A0-00 or Sierra 18-3460.

What are the signs that my water pump impeller needs replacing?
Key indicators of a failing impeller include a weak or intermittent water stream from the "telltale" outlet, engine overheating alarms, or a noticeable reduction in cooling performance. As a best practice, the impeller should be inspected annually.

How often should the water pump impeller be replaced?
For preventative maintenance, we recommend replacing the impeller and related gaskets every one to two years, or every 100-200 hours of operation. Replacement frequency may depend on operating conditions, such as saltwater versus freshwater use.

What is the advantage of a full kit versus buying just the impeller?
This is a complete service kit that includes the neoprene impeller, housing insert, gaskets, plates, and bolts. Replacing all components simultaneously ensures a proper seal, restores the pump to optimal factory condition, and prevents premature wear or leaks that can occur when reusing old parts.

OEM vs. Aftermarket?
This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.

How fast do you ship and how much does it cost?
We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.

What is your warranty and return policy?
This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused & in original condition); please see our policy page or reach out for instructions.

• Verify that the product images and specifications match your original part. If discrepancies exist—even if your model is listed—do not proceed with the purchase.
• This product is an aftermarket replacement part and is not an OEM component.
• Professional installation is recommended to ensure safety and optimal performance.

• Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
• Fast Global Shipping: Free delivery worldwide in 5–15 days.
• Direct from Manufacturer: Competitive pricing without compromising quality.