Transom Bellows Seal Kit – Fits MerCruiser Bravo 1, 2, 3 Drives (Replaces 30-803100T1, 8M0095485)

Transom Bellows Seal Kit – Fits MerCruiser Bravo 1, 2, 3 Drives (Replaces 30-803100T1, 8M0095485)

This transom bellows and seal repair kit is designed for MerCruiser Bravo I, II, and III stern drives (1988 and newer, serial number 0B664190 & up) and Blackhawk stern drives (1994–1995, serial number 0D469859 & up). It provides a comprehensive solution for replacing worn or damaged bellows, seals, and the gimbal bearing, which are critical for protecting the drive's internal components from water intrusion.

This kit serves as a direct replacement for multiple OEM and aftermarket part numbers, ensuring broad compatibility for a complete transom service.

• Includes all necessary bellows (U-Joint, Exhaust, Shift Cable) for a full replacement.
• Comes complete with a new gimbal bearing and installation hardware kit.
• Engineered to meet or exceed original equipment specifications for 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 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.

Technical Specifications

Package Contents

This comprehensive kit includes the following components:

• 1 x U-Joint Bellows (Replaces OEM 86840A05)
• 1 x Exhaust Bellows Assembly (Replaces OEM 18654A1)
• 1 x Exhaust Tube Assembly (Replaces OEM 78458A1)
• 1 x Shift Cable Bellows Assembly (Replaces OEM 74639A2)
• 1 x Gimbal Bearing Assembly (Replaces OEM 30-862540A3)
• 1 x Water Inlet Hose (Replaces OEM 32-43437)
• 1 x Bravo Installation Kit (Replaces OEM 16755Q1)
• 1 x Set of all required Bellows Clamps and Hardware

Installation Guide

Professional installation is highly recommended. The following steps provide a general overview of the installation process:

1. Safety First: Disconnect the boat's battery before starting any work.
2. Access the Transom: Trim the sterndrive to the full "trailer" position to access the transom assembly.
3. Remove Drive: Detach and remove the sterndrive unit from the bell housing.
4. Remove Old Components: Carefully cut and remove the old U-joint, exhaust, and shift cable bellows. Remove the old clamps and water hose.
5. Inspect & Clean: Thoroughly clean the mounting surfaces on the transom and bell housing, inspecting for any damage.
6. Replace Gimbal Bearing: Use a slide hammer puller to remove the old gimbal bearing. Drive the new bearing into place until it is properly seated.
7. Install New Bellows: Install the new shift cable, exhaust, and U-joint bellows. Ensure they are correctly oriented and seated in their grooves.
8. Secure Bellows: Secure each bellow with the new clamps provided in the kit. Ensure clamps are tight and properly positioned.
9. Install Water Hose: Connect the new water inlet hose.
10. Reinstall Drive: Reinstall the sterndrive assembly, including new gaskets from the installation kit.
11. Final Checks: Lower the drive and turn it lock-to-lock to ensure no binding. Once in the water, check thoroughly for any leaks around the transom assembly.

Troubleshooting & FAQ

How do I confirm this fits my engine?
Please refer to the "Compatible Engine Models" table above. This kit is specifically for MerCruiser Bravo I, II, & III stern drives (1988+, SN 0B664190 and up) and Blackhawk drives (1994-95, SN 0D469859 and up). It is critical to verify your model and serial number range before ordering.

What are the signs that my transom bellows need replacement?
Common symptoms include visible cracks, tears, or dry rot in the rubber bellows; water leaking into the boat's bilge; or a noisy or grinding gimbal bearing, which can be heard when turning the drive. Regular inspection is key to catching issues early.

How often should I replace the bellows?
As a preventative maintenance item, transom bellows should be inspected annually and typically replaced every 5-7 years. However, if you operate in saltwater or harsh conditions, more frequent replacement may be necessary.

Is this a complete kit?
Yes, this is a comprehensive kit that includes the U-joint bellows, exhaust bellows, shift cable bellows, gimbal bearing, water hose, gaskets, and all necessary installation clamps and hardware for a standard transom service.

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.