Water Pump Impeller Service Kit – Fits Johnson Evinrude 40-75 HP (Replaces 396725, Sierra 18-3053)
Water Pump Impeller Service Kit – Fits Johnson Evinrude 40-75 HP (Replaces 396725, Sierra 18-3053) 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.).
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Water Pump Impeller Service Kit – Fits Johnson Evinrude 40-75 HP (R...
Product Details
This Water Pump Impeller Service Kit is designed for Johnson and Evinrude 40-75 HP, 2-stroke outboard motors manufactured from 1979 to 2012. It is specifically intended for applications with a large gearcase that utilizes a six-vane impeller design, including various Loopcharged models.
It serves as a direct replacement for Johnson/Evinrude parts 396725, 437080, 777820, 389557, and 432954, as well as aftermarket equivalents Sierra 18-3053, GLM 89710, Mallory 9-45207, and SEI 96-366-03BE.
- Engineered with a robust, marine-grade CR neoprene rubber impeller for durability and reliable cooling performance.
- Fits large gearcase models requiring a plastic wedge-style drive key.
- Includes the essential impeller, drive key, and seals needed for a complete service.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket brands.
| Brand | Part Number |
|---|---|
| Johnson/Evinrude | 396725 / 0396725 |
| Johnson/Evinrude | 437080 / 0437080 |
| Johnson/Evinrude | 777820 / 0777820 |
| Johnson/Evinrude | 389557 / 0389557 |
| Johnson/Evinrude | 432954 / 0432954 |
| Sierra | 18-3053 |
| GLM | 89710 |
| Mallory | 9-45207 |
| SEI | 96-366-03BE |
| Red Rhino | JE-214 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This service kit is verified for the following Johnson and Evinrude outboard motors.
| Brand | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|
| Johnson/Evinrude | 40 HP | 2-Stroke | 1999 & Up | 396725 | Large gearcase with six vane impeller |
| Johnson/Evinrude | 45 HP | 2-Stroke | 1995–2005 | 396725 | Large gearcase with six vane impeller |
| Johnson/Evinrude | 50 HP | 2-Stroke | 1986 & Up | 396725 | 2-Cyl Loopcharged, large gearcase with six vane impeller |
| Johnson/Evinrude | 55 HP | 2-Stroke | 1995–2005 | 396725 | Large gearcase with six vane impeller |
| Johnson/Evinrude | 60 HP | 2-Stroke | 1986 & Up | 396725 | 2-Cyl Loopcharged, large gearcase with six vane impeller |
| Johnson/Evinrude (Commercial) | 65 HP | 2-Stroke | 1984 & Up | 396725 | 3-Cyl Loopcharged, large gearcase with plastic wedge key impeller |
| Johnson/Evinrude | 70 HP | 2-Stroke | 1979–2001 | 396725 | 3-Cyl Loopcharged, large gearcase with plastic wedge key impeller |
| Johnson/Evinrude | 75 HP | 2-Stroke | 1979–1988 | 396725 | 3-Cyl Loopcharged, large gearcase with plastic wedge key impeller |
Technical Specs
- Product Type
- Water Pump Impeller Service Kit
- Material
- Marine Grade CR Neoprene Rubber Impeller
- Includes
- Rubber Impeller, Drive Shaft Key, Seal O-rings and Gaskets
- Key Type
- Plastic Wedge Key
- Impeller Design
- Six Vane
- Compatibility
- Johnson/Evinrude Outboard Motors with Large Gearcase, Large Water Pump
- Other Technical Attributes
- Loopcharged applications
What’s in the Box
- 1 x Rubber Impeller (Replaces 396725/0396725)
- 1 x Plastic Wedge Drive Shaft Key (Replaces 0331901/0334897)
Installation Notes
- Safety First: Disconnect the battery and spark plug wires to prevent accidental starting.
- Drain Gear Oil: Place a drain pan under the lower unit and remove the drain/fill screws to empty the gearcase oil.
- Drop the Lower Unit: Remove the bolts securing the lower unit (gearcase) to the engine. Carefully lower it to gain access to the water pump.
- Disassemble Pump: Unscrew the bolts on the water pump housing and slide it off the driveshaft to expose the old impeller.
- Replace Components: Remove the old impeller, key, gaskets, and seals. Clean all mating surfaces thoroughly before installing the new parts from the kit.
- Reassemble: Lubricate the new impeller and housing. Install the new components in reverse order. Ensure the drive shaft key is seated correctly.
- Finalize & Test: Re-install the lower unit, refill with fresh gearcase oil, and reconnect the battery/plugs. Test the engine in water to verify proper water flow from the tell-tale outlet.
Troubleshooting & FAQ
How do I confirm if this kit fits my specific motor model?
The best way is to match your original part number to the ones listed in our Part Number Matrix. While our compatibility table covers most engine ranges, boat manufacturers sometimes use different lower units. Always verify by the part number or by comparing your old impeller to our product photos.
What are the signs of a failing water pump impeller?
Common symptoms include a weak or intermittent stream from the "tell-tale" water outlet, engine overheating alarms, steam from the exhaust, or a melted water pump housing. If you notice any of these, inspect your impeller immediately.
How often should I replace my water pump impeller?
As a preventative maintenance item, it is recommended to inspect the impeller annually and replace it every 1-2 years, or every 100-200 hours of use, depending on operating conditions. More frequent replacement is advised if you operate in sandy, silty, or shallow water.
This kit mentions a "large gearcase." How can I identify if I have one?
The most reliable method is to measure the gearcase torpedo diameter or check your engine's service manual. The large gearcase on these Johnson/Evinrude models typically has a 4-3/4" diameter. If you are unsure, consult a marine mechanic or contact us with your engine's model number.
OEM vs. Aftermarket?
This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9001 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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