438592 Water Pump Repair Kit for Johnson Evinrude 40HP 50HP | JLM Marine

438592 Water Pump Repair Kit for Johnson Evinrude 40HP 50HP | JLM Marine

This comprehensive water pump repair kit is specifically designed for Johnson and Evinrude outboard engines rated at 40HP and 50HP manufactured between 1995 and 2005. Engineered to restore optimal cooling system performance, this kit ensures your engine operates at safe temperatures and maintains peak efficiency on the water.

This kit directly replaces OEM part number 438592, providing a reliable aftermarket solution for routine maintenance or emergency repairs. It includes all essential components needed for a complete water pump service, along with critical maintenance items to keep your outboard running smoothly.

• Complete repair kit with water pump components, thermostat, fuel filter, and gear oil pump
• Fits both 40HP and 50HP Johnson/Evinrude models from 1995 to 2005
• Includes drain screw gaskets and thermostat gasket for comprehensive service

Part Number Cross-Reference

Use this table to confirm the OEM part number for your Johnson/Evinrude outboard:

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

This comprehensive kit includes the following components:

• 438592 Water Pump Repair Kit × 1
• 436195 Thermostat × 1
• 329830 Thermostat Gasket × 1
• 0398319 Fuel Filter × 1 View Part →
• 311598 Drain Screw Gasket × 2
• 24OP149 Gear Oil Pump × 1

Installation Guide

1. Preparation: Disconnect the fuel line and remove the lower unit from the outboard engine following your service manual. Drain any remaining water from the cooling system.
2. Remove Old Components: Detach the water pump housing and carefully remove the old impeller, gaskets, and seals. Inspect the housing for scoring or damage that may affect new parts.
3. Clean Surfaces: Thoroughly clean all mating surfaces on the pump housing and driveshaft housing to ensure proper sealing. Remove all old gasket material and debris.
4. Install New Impeller: Lubricate the new impeller with glycerin or soapy water (never petroleum-based products). Install the impeller onto the driveshaft with blades oriented in the correct rotation direction.
5. Install Gaskets and Seals: Position new gaskets and seals from the kit onto the housing. Ensure all components are properly aligned and seated.
6. Reassemble Water Pump: Carefully install the water pump housing over the impeller, ensuring blades fold correctly during installation. Torque all fasteners to manufacturer specifications.
7. Replace Thermostat: Remove the old thermostat from the cylinder head and clean the mounting surface. Install the new thermostat (436195) with the provided gasket (329830) in the correct orientation.
8. Install Fuel Filter: Replace the old fuel filter with the new 0398319 fuel filter included in the kit. Ensure fuel line connections are tight and leak-free.
9. Replace Drain Screw Gaskets: Install the two new 311598 drain screw gaskets on the lower unit drain and fill plugs to prevent gear oil leaks.
10. Refill Gear Oil: Use the included 24OP149 gear oil pump to refill the lower unit with appropriate marine gear oil until it flows from the upper vent hole.
11. Reinstall Lower Unit: Align the lower unit with the driveshaft and water tube, then secure all mounting bolts. Reconnect the fuel line and check all connections.
12. Test Operation: Run the engine in a test tank or on the water, checking for proper cooling water discharge from the telltale. Monitor engine temperature and inspect for any leaks.

Troubleshooting & FAQ

Q: How do I confirm this kit fits my specific Johnson or Evinrude engine?
A: Verify that your engine is a 40HP or 50HP model manufactured between 1995 and 2005. Cross-reference the OEM part number 438592 with your service manual or existing water pump kit. If your model year and horsepower match the compatibility table above, this kit will fit your engine.

Q: How often should I replace the water pump impeller and components?
A: Most manufacturers recommend replacing the water pump impeller every 2-3 years or 200-300 hours of operation, whichever comes first. If you notice overheating, reduced water flow from the telltale, or operate in sandy/silty water, inspect and replace components more frequently.

Q: What are the signs that my water pump is failing?
A: Common symptoms include weak or no water discharge from the telltale port, engine overheating, steam from the engine, loss of power, or an overheating alarm. If you experience any of these issues, inspect and replace the water pump components immediately to prevent engine damage.

Q: Can I install this kit myself or do I need a professional mechanic?
A: If you have mechanical experience and the proper tools, you can install this kit following your engine's service manual. However, proper alignment of the water tube and correct impeller orientation are critical. If you're uncertain, professional installation is recommended to ensure reliable cooling system performance.

Q: What's the difference between this aftermarket kit and the original OEM part?
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.