Water Pump Impeller – Fits Johnson/Evinrude 4-8 HP Outboards (Replaces 389576, 433914)
Water Pump Impeller – Fits Johnson/Evinrude 4-8 HP Outboards (Replaces 389576, 433914) is backordered and will ship as soon as it is back in stock.
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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).
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Water Pump Impeller – Fits Johnson/Evinrude 4-8 HP Outboards (Repla...
Product Details
This Water Pump Impeller – Fits Johnson/Evinrude 4-8 HP Outboards (Replaces 389576, 433914) is an essential replacement part for maintaining your engine’s cooling system. It is designed for Johnson/Evinrude 4–8 HP outboard engines, covering 2-Stroke models from 1980–1997 and 4-Stroke models from 1998 and newer.
It serves as a direct replacement for Johnson/Evinrude part number 389576 and interchanges with Sierra 18-3091, Mallory 9-45214, GLM 89500, and CEF 500354.
- Engineered for direct drop-in installation.
- Constructed from durable neoprene rubber for reliable performance.
- Features a robust brass hub for secure engagement.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Johnson/Evinrude | 389576 / 0389576 |
| Sierra | 18-3091 |
| Mallory | 9-45214 |
| GLM | 89500 |
| CEF | 500354 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Johnson/Evinrude | Outboard | 4 | 2-Stroke | 1986–1992 | 389576 | - |
| Johnson/Evinrude | Outboard Deluxe | 4 | 2-Stroke | 1980–1997 | 389576 | - |
| Johnson/Evinrude | Outboard | 4.5 | 2-Stroke | 1980–1997 | 389576 | - |
| Johnson/Evinrude | Outboard | 5 | 2-Stroke | 1980–2001 | 389576 | - |
| Johnson/Evinrude | Outboard | 5 | 4-Stroke | 1998 & up | 389576 | - |
| Johnson/Evinrude | Outboard | 6 | 2-Stroke | 1984–2005 | 389576 | - |
| Johnson/Evinrude | Outboard | 6 | 4-Stroke | 1998 & up | 389576 | - |
| Johnson/Evinrude | Outboard | 8 | 2-Stroke | 1986–1997 | 389576 | - |
| Johnson/Evinrude | Outboard | 8 | 4-Stroke | 1980–2005 | 389576 | - |
Technical Specs
- Product Type
- Water Pump Impeller
- Installation
- Direct Drop-in Replacement
- Material
- Neoprene Rubber with Brass Hub
- Number of Blades
- 6
- Dimensions
- 38.4 mm diameter × 17.9 mm height (1.51 × 0.70 inches)
- Hub Shaft Diameter
- 11.2 mm (0.44 inches)
- Weight
- 34 g (1.2 oz)
- Color
- Black
What’s in the Box
- 1 x Water Pump Impeller (389576/0389576)
Installation Notes
- Disconnect the spark plug leads and shift the engine into neutral.
- Place a drain pan under the lower unit and remove the gearcase drain/fill screws to empty the gear lube.
- Remove the bolts securing the lower unit (gearcase) to the upper driveshaft housing.
- Carefully separate the lower unit, taking care not to damage the driveshaft or shift rod.
- Unbolt and lift the water pump housing to expose the old impeller. Note the rotational direction of the existing impeller blades.
- Remove the old impeller, woodruff key, wear plate, and gaskets.
- Clean the interior of the pump housing and the mounting surfaces thoroughly.
- Install the new wear plate and gasket. Place the new woodruff key on the driveshaft flat spot.
- Slide the new impeller onto the driveshaft, aligning its keyway with the woodruff key. Turn the driveshaft clockwise while pushing down to seat the impeller and bend the blades correctly.
- Apply a new gasket to the housing and reinstall it over the impeller. Tighten bolts to the manufacturer's torque specification.
- Reassemble the lower unit to the engine housing and refill with the correct type and amount of marine gear lube.
- Reconnect spark plug leads and test the engine using a water supply (flushing muffs or in the water), confirming a strong stream from the tell-tale port.
Troubleshooting & FAQ
How do I confirm this impeller fits my outboard?
The most reliable method is to cross-reference your engine's model number and year against the compatibility chart. If you are unsure, compare the dimensions listed in the "Technical Specs" with your old part before ordering.
What are the signs of a worn or failed impeller?
Key indicators include the engine overheating at idle or low speeds, a weak or intermittent water stream from the "tell-tale" outlet port, or a noticeable drop in water pressure. Upon inspection, a bad impeller may have cracked, brittle, or missing blades.
How often should a water pump impeller be replaced?
As a crucial part of preventative maintenance, it is recommended to replace the impeller every one to two years, or every 100-200 hours of operation, regardless of its visible condition. This helps prevent unexpected overheating and engine damage.
Will this aftermarket part perform like the original?
Yes. This impeller is manufactured from high-quality neoprene rubber and a corrosion-resistant brass hub, designed to meet or exceed original equipment manufacturer (OEM) specifications for cooling performance and service life in marine environments.
Can I install this impeller myself?
While many boat owners with mechanical experience perform this task, it requires specific tools and procedural knowledge. If you are not comfortable disassembling the lower unit of your outboard, we recommend professional installation to ensure proper function and avoid damage.
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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