Upper Gearcase Seal Kit – Fits MerCruiser Bravo I, II, III, X, XR, XZ & Blackhawk Stern Drives

Upper Gearcase Seal Kit – Fits MerCruiser Bravo I, II, III, X, XR, XZ & Blackhawk Stern Drives

This complete aftermarket seal kit contains the necessary components to reseal the upper gearcase on MerCruiser Bravo stern drives. It is compatible with Bravo I, II, and III models from 1988 and up, as well as Bravo X, XR, XZ, and the Blackhawk variant (1994-1995).

This kit is a direct replacement for MerCruiser part numbers 26-16709A1 and 26-16709A2.

• Complete Kit: Includes all necessary seals, O-rings, and gaskets for a full upper unit reseal.
• Wide Compatibility: Fits a broad range of MerCruiser Bravo and related stern drives produced since 1988.
• OEM-Spec Installation: All components are manufactured to meet or exceed original equipment specifications for a precise fit.

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

This kit includes: 1 x O-Ring (25-45710), 1 x O-Ring (25-48171), 2 x O-Ring (25-62705), 1 x O-Ring (25-35027), 1 x Seal (16755Q1), 2 x Outdrive Seal (12-19183), 1 x Gear Housing Drain Screw Gasket (12708), 1 x Spring Kit (24-17997A1), 1 x Oil Seal (12709), 1 x Oil Seal (26-807006), 4 x Keeper (97351), 1 x O-Ring (25-97387), 2 x O-Ring (29845), 1 x O-Ring (861844), 1 x O-Ring (25-70937), 1 x O-Ring (20826), 1 x O-Ring (69201).

Installation Guide

1. Drain Gear Lube: Position a drain pan below the gearcase and remove the drain/fill screws to empty the oil.
2. Separate Drive Units: Remove the bolts securing the upper driveshaft housing to the lower unit and carefully separate them.
3. Disassemble Housing: Systematically disassemble the upper gearcase, taking note of the order and orientation of all internal components.
4. Remove Old Seals: Carefully extract all old O-rings, seals, and gaskets from the housing components.
5. Clean and Inspect: Thoroughly clean all sealing surfaces and component bores, ensuring they are free of corrosion, debris, and old sealant.
6. Install New Components: Lightly lubricate and install the new seals and O-rings from the kit, ensuring they are seated correctly without twisting or damage.
7. Reassemble Gearcase: Reassemble the upper gearcase components in the reverse order of disassembly, following manufacturer torque specifications.
8. Refill with Gear Lube: Reattach the upper and lower units, and then fill the gearcase with the correct type and amount of marine gear lube from the bottom-up to prevent air pockets.

Troubleshooting & FAQ

How do I confirm this kit fits my engine?
This kit is designed for MerCruiser Bravo I, II, and III models from 1988 and up, as well as Bravo X, XR, XZ, and Blackhawk (1994-1995) stern drives. To ensure a correct fit, please review the "Compatible Engine Models" table and cross-reference your original part number with those listed in the "Part Number Cross-Reference" section (e.g., 26-16709A1, 26-16709A2).

What are the signs that my upper gearcase seals are failing?
Common indicators of failing seals include visible oil leaks around the upper housing, water intrusion into the gear lube (which gives the oil a milky or cloudy appearance), or a recurring low gear lube level without an obvious external leak.

Is this a complete kit for resealing the upper gearcase?
Yes, this is a comprehensive kit containing the necessary seals, gaskets, and O-rings to completely reseal the upper driveshaft housing on all compatible MerCruiser Bravo models.

OEM vs. Aftermarket?
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.

How fast do you ship and how much does it cost?
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.

What is your warranty and return policy?
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.