MerCruiser Bellows R&R - Fast & Simple

Introduction

This tutorial provides a step-by-step guide on how to remove and replace the U-joint bellows in a MerCruiser Alpha One Gen 2 outdrive system. Unlike other methods that require disassembly, this approach allows you to work with the gimbal intact, making the process simpler and more efficient.

Step 1: Remove the Old U-Joint Bellows

1. Inspect the Old Bellows: Look for any visible tears or damage. This will inform you about the condition and necessity of replacement.
2. Extract the Old Bellows: Carefully pull the old U-joint bellows out. Take note of how it was seated to ensure proper installation of the new one.

Step 2: Prepare for Installation

1. Remove the Spiral Ring: The new bellows comes with a spiral metal wire that stiffens it. Remove this wire to make it easier to install the bellows.
2. Apply Adhesive: Use 3M Yellow Super Weatherstrip and Gasket Adhesive. Apply it generously on the inside lip of the new bellows where it will make contact with the transom housing.
3. Position the Bellows: Insert the bellows into the opening. You may need to bend it slightly to fit it through.

Step 3: Adjust the Bellows

1. Disconnect Exhaust Bellows: If the exhaust bellows are obstructing, disconnect them to create more space for maneuvering.
2. Rotate and Align: Tilt the bellows to position it correctly. Make sure the metal prong on the bellows is at the bottom and the marked top is facing up.
3. Pre-Place the Clamp: Position the metal clamp on the flange where the bellows will sit, ensuring the tightening screw is accessible (at around the 1 to 2 o'clock position).

Step 4: Secure the Bellows

1. Insert and Push: Carefully push the bellows onto the transom housing until it fits snugly.
2. Tighten the Clamp: Use a flexible nut driver (8mm or 5/16 socket) to tighten the clamp securely. Ensure it fits in the groove designed for the clamp.

Step 5: Install the New Ring

1. Apply Adhesive to the Groove: Before placing the new ring, apply adhesive into the groove of the transom housing.
2. Position the Bellows: Pull the bellows into the correct position where the raised area fits into the groove.
3. Drive the Ring In: Use a tool (like a broken piston or a rubber mallet) to tap the new ring into place, ensuring it seals properly.

Step 6: Reattach the Exhaust Bellows

1. Prepare the Exhaust Bellows: Since no adhesive is necessary, simply align and push the exhaust bellows back into place.
2. Create a Custom Tool for Tightening: If needed, make a tool using a threaded rod and fender washers to pull the exhaust bellows into position.
3. Tighten the Clamp: Secure the exhaust bellows clamp to finalize the installation.

Conclusion

You've successfully replaced the U-joint bellows in a MerCruiser Alpha One Gen 2 outdrive system without disassembling the gimbal. Make sure to check your work and ensure everything is secure. If you encounter any issues or have questions, refer to the comments section of the video or consider consulting a marine technician for further assistance. Happy boating!