Water Pump Impeller – Fits Yamaha 2HP Outboard Engines (Replaces 646-44352-01-00)
Water Pump Impeller – Fits Yamaha 2HP Outboard Engines (Replaces 646-44352-01-00) 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 Impeller – Fits Yamaha 2HP Outboard Engines (Replaces 646-44352-01-00) is designed for a precise fit on Yamaha 2HP 2-Stroke (1984–2019) outboard engines, including models 2C, 2CMH, and 2DMH. It also fits specific Mariner 2HP 2-Stroke (1978–1985) outboards with serial numbers beginning with 6A1 and 646.
It serves as a direct replacement for Sierra 18-3072, Mallory CEF500324, GLM 89850, Mariner 47-80395M, and Yamaha 646-44352-01-00.
- Installs directly using the existing key drive.
- Molded from durable, high-quality neoprene rubber for reliable performance.
- Also included as part of the complete Yamaha water pump repair kit 6GD-W0078-00.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket brands.
| Brand | Part Number |
|---|---|
| Yamaha | 646-44352-01-00 / 6464435201 |
| Sierra | 18-3072 |
| Mallory | CEF500324 |
| GLM | 89850 |
| Mariner | 47-80395M / 80395M |
Engine & Model Compatibility
Confirm your engine model and year in the table below.
For Yamaha engines, this impeller fits 2HP models from 1984 to 2019.
For Mariner engines, this part is compatible with 2HP models from 1978 to 1985 having serial numbers that start with 6A1 or 646.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Yamaha | 2C | 2 | 2-Stroke | 1984–2016 | 646-44352-01-00 | |
| Yamaha | 2CMH | 2 | 2-Stroke | 1984–2016 | 646-44352-01-00 | |
| Yamaha | 2DMH | 2 | 2-Stroke | 2016–2019 | 646-44352-01-00 | |
| Mariner | 2HP | 2 | 2-Stroke | 1978–1985 | 47-80395M/80395M | Serial numbers beginning with 6A1 & 646 |
Technical Specs
- Product Type
- Water Pump Impeller
- Installation
- Direct replacement with key drive
- Housing Material
- Neoprene rubber
- Dimensions
- Outside Diameter: 47.5 mm (1.875"), Inside Diameter: 11.15 mm (0.438"), Height: 13.7 mm
- Number of Blades
- 6
- Shaft Diameter
- 11.15 mm key drive
What’s in the Box
- 1 x Impeller (Replaces 646-44352-01-00)
Installation Notes
- Disconnect the spark plug wire(s) and battery cables for safety.
- Place the outboard in neutral and remove the bolts securing the lower unit (gearcase).
- Carefully lower and separate the gearcase from the upper housing, disconnecting the shift shaft if necessary.
- Locate the water pump housing on top of the gearcase and remove its bolts.
- Slide the housing up to expose the old impeller. Note the rotational direction of the old blades.
- Remove the old impeller, key, and gaskets. Clean all mating surfaces thoroughly.
- Install the new key and slide the new impeller onto the driveshaft. Turn the driveshaft clockwise while pushing down to bend the blades correctly.
- Apply a light coat of marine grease to the new gaskets and install them.
- Reinstall the water pump housing, ensuring a tight seal.
- Reattach the lower unit, ensuring the driveshaft, shift shaft, and water tube align correctly. Secure with bolts.
- Reconnect the spark plug wire(s) and battery.
- Start the engine in a test tank or with a water flusher to verify proper water flow from the tell-tale outlet.
Troubleshooting & FAQ
How can I tell if this impeller will fit my engine?
The surest way is to match your engine's model, horsepower (HP), and year to the "Engine & Model Compatibility" table. For some brands like Mariner, the serial number range is also critical. Always verify the OEM part number if possible.
What are the signs of a failing water pump impeller?
Common signs include the engine overheating at idle or low speeds, a weak or non-existent water stream from the "tell-tale" outlet, and a dry, cracked, or deformed appearance upon inspection.
How often should I replace my impeller?
For preventative maintenance, it's a best practice to replace the impeller every 1–2 years or every 100–200 hours of operation, whichever comes first. This interval may be shorter if you frequently operate in sandy, silty, or saltwater conditions.
Is this impeller difficult to install?
Installation requires basic mechanical skills and tools to remove the lower unit. While many boat owners perform this service themselves, we recommend professional installation if you are not comfortable with the process to ensure safety and correct function.
OEM vs. Aftermarket?
This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.
Shipping speed & cost
We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.
Warranty & returns
Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in 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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