393630 Water Pump Repair Kit for Johnson/Evinrude | JLM Marine

393630 Water Pump Repair Kit for Johnson/Evinrude – Complete Maintenance Solution

This comprehensive water pump repair kit is engineered for Johnson/Evinrude outboard motors ranging from 20HP to 35HP across model years 1980–2005. Designed to restore reliable cooling system performance, this kit ensures your engine operates at optimal temperature under demanding marine conditions.

Direct replacement for OEM part number 393630, this kit provides all essential components for a complete cooling and lubrication system service in one package.

• Includes water pump repair kit, thermostat, fuel filter, gaskets, and gear oil pump for comprehensive maintenance
• Fits multiple horsepower ranges across two decades of Johnson/Evinrude models
• All components meet OEM specifications for reliable, long-lasting performance

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 Serial Number Guide.

Technical Specifications

Package Contents

This complete maintenance kit includes the following components:

• 393630 Water Pump Repair Kit × 1
• 5005440 Thermostat × 1
• 0398327 Fuel Filter × 1 View Part →
• 0327674 Cylinder Head Cover Gasket × 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 motor according to your service manual. Drain all existing gear oil completely.
2. Remove Old Components: Disassemble the existing water pump housing and carefully remove the old impeller, gaskets, and seals. Clean all mating surfaces thoroughly to ensure proper sealing.
3. Install Water Pump Kit: Follow the instructions included with part 393630 to install the new impeller, plate, and housing gaskets. Apply marine-grade grease to the impeller before installation.
4. Replace Thermostat: Remove the old thermostat housing and install the new 5005440 thermostat with a fresh gasket. Ensure proper orientation per your engine's specifications.
5. Install Cylinder Head Gasket: Replace the cylinder head cover gasket (0327674) ensuring proper alignment with all bolt holes. Torque fasteners to manufacturer specifications in a cross pattern.
6. Replace Drain Screw Gaskets: Install both new 311598 drain screw gaskets on the lower unit drain and fill plugs. Do not overtighten to avoid crushing the gaskets.
7. Install Fuel Filter: Replace the existing fuel filter with the new 0398327 filter in the fuel line. Ensure the arrow on the filter points toward the engine.
8. Add Gear Oil: Using the 24OP149 gear oil pump, fill the lower unit with the recommended marine gear oil through the lower drain hole until oil appears at the upper vent hole.
9. Reassemble Lower Unit: Reinstall the lower unit to the motor, ensuring the driveshaft engages properly. Tighten all mounting bolts to specified torque values.
10. Final Checks: Reconnect the fuel line and inspect all connections for leaks. Start the engine and verify water flow from the telltale indicator.
11. Test Run: Run the engine in a test tank or on-water for 10–15 minutes, monitoring operating temperature and water pump discharge. Check for any fuel or gear oil leaks.

Troubleshooting & FAQ

Q: How do I confirm this kit fits my specific Johnson/Evinrude engine?
A: Cross-reference your engine's horsepower and year with the compatibility table above. Verify your original water pump uses OEM part number 393630, and use the Johnson Serial Number Guide linked above to confirm your model year.

Q: How often should I replace the water pump and these components?
A: Water pump impellers should typically be replaced every 2–3 years or 200–300 hours of operation, whichever comes first. The fuel filter should be changed annually, while gaskets and the thermostat should be inspected during each water pump service and replaced as needed.

Q: What are the signs that my water pump needs replacement?
A: Common symptoms include reduced or no water discharge from the telltale indicator, engine overheating, weak water stream, or unusual noise from the lower unit. If you notice any of these signs, inspect and replace the water pump immediately to prevent engine damage.

Q: Can I install this kit myself or do I need a professional?
A: If you have mechanical experience and the proper tools, this installation can be completed in 2–3 hours. However, it requires lower unit removal and precise torque specifications. Professional installation is recommended if you're unfamiliar with outboard service procedures.

Q: Does this kit include everything I need for a complete water pump service?
A: This package includes the water pump repair kit and related maintenance components (thermostat, fuel filter, gaskets, and gear oil pump). You will need to supply marine-grade grease for the impeller and gear oil for refilling the lower unit.

Q: What's the difference between OEM and aftermarket parts?
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.