Water Pump Impeller Kit – Fits Johnson/Evinrude 4-8 HP 1980+ (Replaces 396644, 0396644)

Water Pump Impeller Kit – Fits Johnson/Evinrude 4-8 HP 1980+

This water pump impeller service kit is designed for Johnson/Evinrude 4 HP to 8 HP 2-stroke outboard motors manufactured from 1980 to 2005. Compatible applications include 4 HP Deluxe (1985–1992), 4.5 HP (1980–1984), 5 HP (1980–1983, 1986–2001), 6 HP (1984–2001, 2003–2005), and 8 HP (1980–2001, 2003–2005).

This kit serves as a direct replacement for Johnson/Evinrude part numbers 396644 / 0396644, Sierra 18-4529, and GLM Marine 12065.

• Includes all necessary components for a full water pump rebuild: impeller, housing, plate, gasket, key, and hardware.
• Engineered to meet or exceed OEM specifications for reliable cooling performance.
• Constructed with a durable Nylon PA66 plastic housing for longevity.

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

• 1 x Impeller Assembly (Replaces 389576 / 18-3091)
• 1 x Impeller Housing Plate (Replaces 324640 / 18-4578)
• 1 x Impeller Housing Cup (Replaces 324641 / 18-4551)
• 1 x Impeller Housing Gasket (Replaces 325040 / 18-99156)
• 1 x Drive Key (Replaces 331130 / 18-3026)
• 1 x Grommet (Replaces 321129 / 18-1827)
• 1 x Grommet (Replaces 302497 / 18-3329)
• 2 x Stainless Steel Screws (Replaces 324430 / 18-4277)
• 1 x O-Ring (Replaces 303191 / 18-7413)

Installation Guide

1. Disconnect the negative battery cable and remove the lower unit (gearcase) from the outboard motor.
2. Locate and unbolt the screws securing the water pump housing.
3. Carefully lift off the old housing. Remove the impeller, drive key, and wear plate.
4. Thoroughly clean all mating surfaces, removing any old gasket material or debris.
5. Install the new wear plate and gasket, ensuring proper alignment.
6. Slide the new impeller drive key into place on the driveshaft.
7. Install the new impeller, turning the driveshaft clockwise to seat the vanes correctly inside the new housing cup.
8. Place the new housing assembly over the impeller and align the bolt holes.
9. Lightly grease and install the new screws, tightening them evenly in a crisscross pattern to the manufacturer's specified torque.
10. Reinstall the lower unit on the outboard, ensuring the water tube and driveshaft are properly aligned.
11. Reconnect the battery and test the engine in the water, confirming a steady stream from the tell-tale outlet.

Troubleshooting & FAQ

Q: How do I confirm this impeller kit fits my Johnson/Evinrude engine?

A: The best way is to verify your engine's horsepower and year fall within the ranges listed in the "Compatible Engine Models" table. For certainty, cross-reference your existing part number with the OEM numbers provided (396644 / 0396644).

Q: What are the signs of a failing water pump impeller?

A: The most common signs are the engine overheating, a weak or non-existent water stream from the "tell-tale" outlet, or a high-pitched whining sound from the lower unit. Visual inspection may reveal cracked, brittle, or worn impeller vanes.

Q: How often should I replace my water pump impeller?

A: For optimal engine protection, we recommend inspecting the impeller annually and replacing it every 1-2 years as part of regular maintenance. If you frequently operate in saltwater or water with high levels of sand or silt, consider replacing it more often.

Q: Is this a complete kit, or will I need to reuse old parts?

A: This is a complete repair kit that includes a new impeller, housing, plate, cup, and all the necessary gaskets, grommets, and hardware for a full replacement. You should not need to reuse any old components.

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.