Water Pump Impeller Kit – Fits Johnson/Evinrude 4HP Outboards

Water Pump Impeller Kit – Fits Johnson/Evinrude 4HP Outboards (Replaces 436737, 0436737)

This water pump impeller repair kit is designed for Johnson/Evinrude OMC 4HP, 2-Stroke, 1993–1996 models with gearcase codes E4RD, BE4RDHL, and similar model variants. It provides a comprehensive solution for maintaining your outboard's cooling system.

It serves as a direct replacement for multiple part numbers, ensuring compatibility across different brands and providing a reliable restoration of the engine's cooling circuit.

• Complete kit includes the impeller, housing, gaskets, and necessary hardware for a full service.
• Engineered for direct installation, matching OEM fit and function.
• Restores cooling system performance to prevent engine overheating and ensure reliability.

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 Water Pump Housing and Drive Key (331130)
• 1 x Impeller Assembly
• 1 x Impeller Housing Plate (324640)
• 1 x Impeller Housing Cup (324641)
• 1 x Impeller Housing Gasket (325040)
• 1 x O-Ring (303191)
• 2 x Gasket (311598)
• 1 x Grommet (321129)
• 1 x Grommet (302497)
• 1 x Screws (324430)

Installation Guide

1. Disconnect the Battery: Ensure the engine's battery is disconnected to prevent accidental starting.
2. Access the Lower Unit: Position the outboard securely and remove the bolts connecting the gearcase (lower unit) to the engine leg.
3. Remove Old Pump: Carefully slide the lower unit down. Unbolt and remove the existing water pump housing to access the old impeller and gaskets.
4. Clean Surfaces: Thoroughly clean the mounting surfaces on the gearcase and the base of the old pump housing, removing any old gasket material or debris.
5. Install New Components: Install the new impeller key, impeller (rotate shaft clockwise to bend vanes correctly), gaskets, and wear plate according to the diagram.
6. Install New Housing: Place the new housing cup and housing over the impeller assembly and secure it with the provided screws.
7. Reassemble Lower Unit: Carefully align and slide the lower unit back into place, ensuring the driveshaft and water tube are properly seated. Reinstall and tighten the bolts.
8. Test Operation: Reconnect the battery. Start the engine using a flush-muff or in the water to verify that water is discharging from the pilot outlet.

Troubleshooting & FAQ

Q: How do I know if this kit fits my 4HP Deluxe model?

A: This kit is confirmed for 4HP Deluxe models from 1989-1996. However, due to variations in early production years, we strongly advise verifying compatibility by matching your existing part numbers and visual details with the photos and diagrams provided before purchase.

Q: Does this repair kit include the water pump housing?

A: Yes. As shown in the "Package Contents" list, this is a comprehensive kit that includes the water pump housing, impeller, plate, gaskets, and other necessary components for a full replacement. Some other aftermarket kits with the same part number may not include the housing.

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

A: Common symptoms include a weak or non-existent water stream from the "tell-tale" outlet, an engine overheating alarm, or a noticeable drop in engine performance. A worn or damaged impeller cannot effectively pump cooling water.

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

A: For preventative maintenance, 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 (e.g., saltwater vs. freshwater).

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.