26-76868A04 Lower Gear Case Seal Kit for MerCruiser Bravo I II III X | JLM Marine

Lower Gear Case Seal Kit for MerCruiser Bravo I II III X | 26-76868A04

This comprehensive lower gear case seal kit is engineered for MerCruiser Bravo series stern drives, including Bravo I, II, III, and X models from 1988 to 2013. Designed to restore proper sealing in your lower unit gearcase, this kit provides all essential O-rings and seals needed for professional-grade repairs and maintenance.

This aftermarket replacement directly cross-references Mercury MerCruiser 26-76868A04, 26-76868A1, 26-76868A2, OMC/Johnson/Evinrude 0508970, and Sierra 18-2645-1, ensuring broad compatibility across multiple part numbering systems.

• Complete seal and O-ring set for lower unit gearcase repair
• Fits Bravo One, Two, Three, and X series stern drives
• Includes driver repair installer components for proper seal installation

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 Mercury owners, here's a guide to help you identify your engine's serial/model: Mercury Serial Number Guide. You can also review exploded diagrams to verify part numbers: Mercury Parts Diagrams & Catalog.

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 kit includes:

• 1 × Lower Unit Seal Kit (all parts as shown in product images)
• Complete set of O-rings and seals for lower gearcase
• Driver repair installer tools for proper seal installation

Installation Guide

1. Disconnect the battery and remove the stern drive unit from the boat following manufacturer service manual procedures.
2. Drain all gear oil from the lower unit and clean the exterior surfaces thoroughly.
3. Separate the lower gearcase from the upper housing, taking care to note the orientation of all components.
4. Remove the old seals and O-rings from their grooves, inspecting all seal surfaces for damage or corrosion.
5. Clean all seal mating surfaces with a suitable solvent and dry completely.
6. Lightly lubricate new seals and O-rings with marine-grade grease before installation.
7. Use the provided installer tools to seat each seal evenly without twisting or pinching.
8. Verify that all O-rings are properly seated in their grooves and not twisted.
9. Reassemble the lower unit to the upper housing, ensuring proper alignment and torque specifications per service manual.
10. Refill the gearcase with the manufacturer-recommended gear oil to the proper level.
11. Reinstall the stern drive unit onto the boat and reconnect all hardware securely.
12. Test the drive in water and check for leaks before resuming normal operation.

Troubleshooting & FAQ

Q: How do I confirm this seal kit fits my Bravo drive?
A: Check the compatibility table above for your specific Bravo model and year. Verify your stern drive's model designation (stamped on the unit) matches one of the listed applications. If uncertain, cross-reference the OEM part number 26-76868A04 in your service manual or parts diagram.

Q: What are the signs that my lower unit seals need replacement?
A: Common symptoms include visible gear oil leaks around the lower unit, water contamination in the gear oil (milky appearance), difficulty shifting gears, or unusual noise from the gearcase. Regular inspection during oil changes can catch seal deterioration early.

Q: How often should I replace the lower unit seals?
A: Replace seals whenever you service the lower unit, typically every 2-3 years or 200 hours of operation, or immediately if you notice leaks or water intrusion. Always install new seals when rebuilding or reassembling the gearcase.

Q: Do I need special tools to install these seals properly?
A: Yes, this kit includes driver and installer tools designed to seat seals evenly without damage. Using the proper tools prevents seal distortion, pinching, or improper seating that can cause premature failure.

Q: Can I reuse old seals if they look okay?
A: No, always replace seals during any lower unit service. Even seals that appear intact lose elasticity and sealing capability over time, and reusing them risks water intrusion and costly damage to internal gears and bearings.

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