Water Pump Impeller – Fits Johnson/Evinrude 40-50 HP (Replaces 432941)

Water Pump Impeller – Fits Johnson/Evinrude 40-50 HP (Replaces 432941)

This water pump impeller is designed for Johnson/Evinrude 2-stroke outboard motors, specifically 40-50 HP models manufactured between 1989 and 1994. It serves as a direct replacement for multiple OEM and aftermarket part numbers, ensuring a precise fit and reliable performance.

This component is crucial for maintaining proper engine cooling by circulating water through the cooling system. It is engineered to meet or exceed original equipment specifications for durability and longevity.

• Installation Method: Direct OEM Replacement
• Material: Durable Neoprene with a Brass Insert
• Blade Count: 6

Part Number Cross-Reference

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

Compatible Engine Models

Confirm your engine model/year in the table below. For Johnson/Evinrude owners, here’s a guide to help you identify your engine’s serial/model: Johnson/Evinrude Serial Number Guide.

Technical Specifications

Package Contents

The package includes:

• 1 x Water Pump Impeller (Replaces 432941)

Explosion Diagram

Installation Guide

1. Disconnect the negative battery cable to prevent accidental starting.
2. Place a drain pan under the lower unit and remove the gear lube drain screw to empty the oil.
3. Unbolt and carefully lower the gearcase assembly from the outboard's driveshaft housing.
4. Remove the water pump housing bolts and slide the housing up and off the driveshaft.
5. Note the rotational direction of the old impeller vanes before removing it.
6. Slide the old impeller off the driveshaft, then remove the old gasket and wear plate.
7. Clean the mating surfaces of the housing and base to ensure a proper seal.
8. Install the new wear plate and gasket, followed by the new impeller. Important: Turn the driveshaft clockwise while pushing down to set the vanes correctly.
9. Apply a light coat of marine grease to the inside of the pump housing and reinstall it.
10. Reattach the gearcase assembly to the driveshaft housing and tighten bolts to spec.
11. Refill the lower unit with the correct gear lube and secure the drain screw.
12. Reconnect the battery and test the engine with a water supply to confirm proper water pump operation.

Troubleshooting & FAQ

Q: How can I verify this impeller is the right part for my motor?
A: Check your current part number against the list in our "Part Number Cross-Reference" section. Also, confirm your engine's model, HP, and year fall within the ranges listed in the "Compatible Engine Models" table. When in doubt, visual comparison with your old part is recommended.

Q: What are common symptoms of a worn or failed impeller?
A: The most common signs are the engine overheating at idle or low speeds, and a weak or nonexistent water stream from the "tell-tale" outlet. Failure to replace a bad impeller can lead to severe engine damage.

Q: How often should I replace my water pump impeller?
A: For preventative maintenance, it is highly recommended to replace the impeller every year or every 100 hours of use, whichever comes first. This is especially important if you frequently operate in sandy, silty, or saltwater conditions.

Q: OEM vs. Aftermarket?
A: 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.

Q: How fast do you ship and how much does it cost?
A: 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.

Q: What is your warranty and return policy?
A: 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.

Important Notes

• 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.

Why Choose JLM MARINE?

• 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.