Lower Unit Seal Kit – Fits Johnson/Evinrude 40-75 HP (Replaces 5000309, 0396349, 0777558)

Lower Unit Seal Kit – Fits Johnson/Evinrude 40-75 HP (Replaces 5000309, 0396349, 0777558)

This comprehensive gearcase seal kit is designed for a wide range of Johnson/Evinrude 2-stroke 40-75 HP outboards (1975–2001) and Evinrude E-TEC 40-60 HP models (2004–2008). It provides all necessary components for a complete lower unit service, ensuring a precise and reliable seal.

This kit directly replaces Johnson/Evinrude part numbers 5000309, 0396349, and 0777558, as well as several common aftermarket equivalents, offering a dependable and cost-effective solution for gearcase maintenance and repair.

• Includes all required seals, O-rings, gaskets, washers, and screws for a full service.
• Engineered as a direct replacement for hassle-free installation.
• Compatible with 2-stroke gasoline outboard engines.

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 kit includes the following components:

• 4 x Washer (0332584/18-7475)
• 4 x Screw Bearing Housing (0320041/0316564/0777794/18-2379)
• 2 x Fill & Drain Screw Seal (0311598/3852105/0777517/18-4248)
• 2 x Fill & Drain Plug Screw (0307551/0027283/0912625/0982851/0777602/18-2387)
• 2 x Upper & lower Seal (0330137/0310600/0321463/0321668/0317761/0313398/0777519/18-2001)
• 1 x Oil Seal (0342786/0769517/18-8325)
• 1 x Driveshaft Oil Retainer (Lower) (0321466/0313337/0318223/0777531/18-2059)
• 1 x Upper Driveshaft Oil Retainer (0332205/0777942/18-2064)
• 1 x Seal (0324937/0313656/0777908/18-2537)
• 1 x Gasket (0336530/0777867/18-2709)
• 1 x Impeller Housing Seal (0324981/0777871/18-7481)
• 1 x Solenoid to Gearcase Gasket (0314082/0320312/0777545/18-2855)
• 1 x O-Ring (0313446/0765593/18-7127)
• 1 x Driveshaft Bearing O-Ring (0313754/0310580/0313734/0777903/18-7128)
• 1 x Crankshaft to driveshaft O-Ring (0326649/0122678/0553127/0777902/18-7174)
• 1 x O-Ring (0318372/0777526/18-7137)
• 1 x Seal (0307853/0765640/18-7120)
• 1 x O-Ring (310967)

Installation Guide

Professional installation is highly recommended. The following are general steps for replacing a lower unit seal kit:

1. Drain Gear Lube: Place a drain pan under the lower unit. Remove the upper (vent) and lower (drain) screws and allow the gear lube to drain completely.
2. Remove Lower Unit: Disconnect the shift linkage (if applicable) and remove the bolts securing the gearcase to the midsection. Carefully lower the unit.
3. Disassemble Gearcase: Take note of the order of components as you disassemble. Remove the water pump housing and impeller, followed by the bearing carrier.
4. Replace Seals and O-Rings: Carefully remove all old seals, gaskets, and O-rings from the driveshaft, shift shaft, and bearing carrier housing. Clean the seating surfaces thoroughly.
5. Install New Components: Lubricate the new seals and O-rings with a light coat of marine grease. Carefully press them into place using an appropriate seal driver or socket, ensuring they are seated correctly and not damaged.
6. Reassemble Gearcase: Reinstall the bearing carrier, water pump, and all other components in the reverse order of disassembly. Torque all fasteners to the manufacturer's specifications.
7. Reinstall Lower Unit: Mount the lower unit back onto the midsection, reconnect the shift linkage, and tighten the mounting bolts to the specified torque.
8. Refill with Gear Lube: Pump fresh marine gear lube into the lower drain hole until it flows out of the upper vent hole. Reinstall the vent plug, then the drain plug, using the new washers provided.
9. Check for Leaks: After running the engine, check for any signs of oil or water leaks around the seals and plugs.

Troubleshooting & FAQ

Q: How do I confirm this kit will fit my specific engine?
A: Start by checking the 'Compatible Engine Models' table on this page. While this kit is designed for the models listed, we strongly recommend comparing the parts in our product photos to your original parts before ordering. Some models within the listed years may have variations, and a visual match is the best way to guarantee fitment.

Q: What are the signs my gearcase seals are failing?
A: Common indicators of a failed seal include visible gear lube leaking from the propeller shaft area or around the drain/vent screws. Another major sign is milky or water-contaminated gear lube when you drain it, which means water is entering the lower unit.

Q: Are there any differences between these seals and the OEM parts?
A: Our aftermarket kits are engineered to meet or exceed OEM specifications for fit and function. However, as noted, there can be slight variations in material or design between OEM and aftermarket versions. Our parts are made from high-quality materials to ensure a durable and long-lasting seal.

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.