Lower Unit Seal Kit – Fits Tohatsu/Nissan 15HP, 20HP, 25HP, 30HP Outboards (Replaces 346650130, 332601030)

Lower Unit Seal Kit – Fits Tohatsu/Nissan 15HP, 20HP, 25HP, 30HP Outboards

This lower unit seal kit is engineered for Tohatsu and Nissan 4-stroke outboard motors in the 15HP to 30HP range. It provides a reliable seal to protect your gearcase from water intrusion and oil leaks, ensuring the longevity and performance of your engine.

This kit is a direct replacement for Tohatsu/Nissan part numbers 346650130 and 332601030.

• Complete Kit: Includes all necessary seals and gaskets for a full lower gearcase service.
• Engine Compatibility: Designed for Tohatsu/Nissan 15HP, 20HP, 25HP, and 30HP (4-Stroke) models.
• Installation Location: Mounts on the lower gearcase unit.

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.

Technical Specifications

Package Contents

• 1 x Complete Lower Unit Seal Kit (includes all required seals and gaskets)

Installation Guide

1. Drain Oil: Start by completely draining the old gearcase oil into a suitable container.
2. Remove Lower Unit: Remove the propeller assembly, then unbolt and detach the entire lower unit from the outboard's midsection.
3. Disassemble: Carefully disassemble the gearcase components, including the bearing carrier and prop shaft, to access the old seals.
4. Remove Old Seals: Using an appropriate seal puller or tool, remove the old prop shaft and driveshaft seals. Note their orientation.
5. Clean Surfaces: Thoroughly clean the seal housings and all mating surfaces. Ensure no old sealant, debris, or corrosion remains.
6. Lubricate New Seals: Lightly coat the new seals with marine grease on the inner and outer lips to ensure smooth installation and a proper seal.
7. Install New Seals: Press the new seals into place using a correctly sized socket or seal driver. Ensure they are seated evenly and at the correct depth.
8. Reassemble: Reassemble the gearcase, making sure to ahere to manufacturer torque specifications for all bolts.
9. Reinstall Unit: Mount the lower unit back onto the engine and reinstall the propeller.
10. Refill Oil: Fill the gearcase with new, manufacturer-recommended lower unit lubricant until it flows out of the upper vent screw. Re-insert both screws securely.
11. Final Check: Check for any signs of oil leaks around the seals before and after running the engine.

Troubleshooting & FAQ

Q: How do I confirm this kit fits my Tohatsu/Nissan engine?

A: This kit is designed for Tohatsu and Nissan 15HP, 20HP, 25HP, and 30HP 4-stroke models. The most reliable way to confirm fitment is to match the OEM part numbers 346650130 or 332601030 with your engine's service manual or existing parts. Please also refer to the compatible models table.

Q: What are the signs that my lower unit seals are failing?

A: Common signs of a bad seal include a milky, white, or gray appearance in your gear lube, which indicates water contamination. You may also notice gear oil leaking from the propeller shaft area or around the lower unit housing.

Q: How often should I replace lower unit seals?

A: It's good practice to inspect the seals for leaks during every annual service. We recommend replacing them as a preventative measure every 3-5 years or anytime the lower unit is being serviced, such as for a water pump replacement.

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.