Impeller – Fits Johnson/Evinrude 25–50 HP (Replaces 432941, 18-3104-1)

$22.99 $36.00

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Impeller – Fits Johnson/Evinrude 25–50 HP (Replaces 432941, 18-3104-1) is backordered and will ship as soon as it is back in stock.

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Product Details

This aftermarket Impeller – Fits Johnson/Evinrude 25–50 HP is a direct-fit replacement water pump component essential for engine cooling. It is designed for a range of Johnson and Evinrude outboard motors, including 35 HP Jet (1992–1993), 40 HP (1989–1998), 48 HP (1989–1996), and 50 HP (1989–1998) 2-stroke models.

It interchanges with Johnson/Evinrude OEM part numbers 432941, 0432941, 437059, 765350, 777825 and Sierra part numbers 18-3104 and 18-3104-1.

Installs as a direct OEM-equivalent replacement.
Engineered with a durable neoprene rubber impeller and a brass or hardened nylon hub.
Package includes the impeller, drive key, and necessary seals for a complete service.

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket.

Brand	Part Number
Johnson/Evinrude	432941 / 0432941
Johnson/Evinrude	437059 / 0437059
Johnson/Evinrude	765350 / 0765350
Johnson/Evinrude	766433 / 0766435
Johnson/Evinrude	777825 / 0777825
Sierra	18-3104 / 18-3104-1

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For Evinrude outboards, this impeller fits various E, TE, and VE models from 35 to 50 HP manufactured between 1989 and 1998.

For Johnson outboards, this part is compatible with select J, TJ, and VJ models from 35 to 50 HP within the 1989–1998 year range.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.
Evinrude	E40	40	2-Stroke	1989–1998	432941
Evinrude	TE40	40	2-Stroke	1989–1998	432941
Evinrude	VE40	40	2-Stroke	1989–1998	432941
Evinrude	E48	48	2-Stroke	1989–1996	432941
Evinrude	VE48	48	2-Stroke	1989–1996	432941
Evinrude	E50	50	2-Stroke	1989–1998	432941
Evinrude	TE50	50	2-Stroke	1989–1998	432941
Evinrude	VE50	50	2-Stroke	1989–1998	432941
Evinrude	35 Jet	35	2-Stroke	1992–1993	432941
Johnson	J40	40	2-Stroke	1989–1998	432941
Johnson	TJ40	40	2-Stroke	1989–1998	432941
Johnson	VJ40	40	2-Stroke	1989–1998	432941
Johnson	J48	48	2-Stroke	1989–1996	432941
Johnson	VJ48	48	2-Stroke	1989–1996	432941
Johnson	J50	50	2-Stroke	1989–1998	432941
Johnson	TJ50	50	2-Stroke	1989–1998	432941
Johnson	VJ50	50	2-Stroke	1989–1998	432941

Technical Specs

Product Type: Water Pump Impeller
Installation: Direct OEM Replacement
Material: Neoprene Rubber with Brass/Hardened Nylon Hub
Blades: 6
Dimensions: Height: 25.4 mm (1.0 in), Diameter: 91.3 mm (3.59 in)
Hub Shaft Diameter: 19.1 mm (0.75 in)
Weight: 68 g (2.4 oz)
Color: Black

What’s in the Box

1 x Water Pump Impeller (Replaces 432941)
1 x Drive Shaft Key
1 x Impeller Housing Seal (Note: may vary by manufacturer)
1 x O-Ring (Note: may vary by manufacturer)

Installation Notes

Disconnect the negative battery cable for safety.
Place a drain pan under the lower unit and remove the gear oil drain/fill screws to empty the oil.
Remove the bolts securing the lower unit (gearcase) to the engine housing.
Carefully lower and remove the gearcase assembly.
Unbolt and remove the water pump housing cover to access the impeller.
Remove the old impeller, noting the rotational direction of the fins. Remove the old drive key.
Thoroughly clean the impeller housing, wear plate, and all mating surfaces.
Install the new O-ring and impeller housing seal.
Insert the new drive shaft key. Align the new impeller and slide it down while turning the driveshaft clockwise to seat the fins correctly.
Reinstall the water pump housing and torque bolts to manufacturer specifications.
Re-install the lower unit, ensuring the water tube and shift shaft are properly aligned.
Refill the lower unit with the correct type and amount of marine gear lubricant.

Troubleshooting & FAQ

How do I know if my impeller is failing?

Common signs of a worn or failed impeller include a weak or non-existent water stream from the "tell-tale" outlet, engine overheating alarms at idle or low speeds, or finding brittle, cracked, or broken fins during a visual inspection.

What is the recommended replacement interval?

For best reliability, inspect your impeller annually. We recommend replacing it every 1 to 2 years or every 100-200 hours of operation, whichever comes first. More frequent replacement may be needed if you operate in sandy, silty, or saltwater conditions.

My old impeller had 3 blades, but this one has 6. Will it fit?

Yes. This 6-blade impeller is designed as the direct, OEM-style replacement for the listed models. While some aftermarket versions may feature a 3-blade design, the 6-blade configuration is the correct standard for these specific engines and ensures proper cooling performance.

Will this fit any Johnson/Evinrude engine?

No. It is critical to verify compatibility. This part is specifically for the 25 HP to 50 HP models and years listed in the compatibility table. Do not purchase if your engine model is not explicitly listed.

What is the difference between a brass and nylon hub?

Both materials are engineered to meet or exceed OEM specifications for durability. Brass offers excellent corrosion resistance, while hardened nylon provides a strong, lightweight alternative. The hub material may vary between different aftermarket manufacturers, but both ensure a secure fit and reliable power transfer from the driveshaft.

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

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Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.

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