Sierra Transom Seal Kit 18-8218 for Mercruiser Bellows

The Sierra Transom Seal Kit, part number 18-8218, is a replacement seal kit designed for Mercruiser bellows applications on sterndrive-equipped boats. The transom assembly is the critical barrier between the outside water and the inside of the boat's hull, and the seals within it are what keep that barrier watertight around the drive shaft, shift cable, and steering components as they pass through the transom. Over time these seals harden, crack, or compress from age and exposure, which is when a full seal kit replacement becomes necessary rather than replacing a single component.

This kit is sold as a complete set so that all of the wear-prone sealing components in the transom assembly are addressed in one service, which is the standard approach for a proper transom rebuild rather than patching individual pieces. It is packaged as a single kit (quantity of one) for straightforward ordering and installation planning.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-8218
• Product Type: Transom Seal Kit
• Application: Mercruiser Bellows
• Weight: 4.26 pounds
• Product Dimensions: 0.39 x 0.39 x 0.39 inches
• UPC: 808282305291
• Package Quantity: One kit

Frequently Asked Questions

What is the Sierra 18-8218 used for? It is a transom seal kit used to reseal the transom assembly on Mercruiser bellows applications, sealing the openings where the drive shaft, shift cable, and steering components pass through the boat's transom.

Is this a complete kit or a single seal? Sierra part number 18-8218 is sold as a complete transom seal kit, packaged as one full set rather than a single individual seal.

How many kits come in an order? Each order of the 18-8218 transom seal kit includes one complete kit.

What does this kit weigh? The Sierra 18-8218 Transom Seal Kit weighs 4.26 pounds.

What are the product dimensions of the 18-8218 kit? The packaged dimensions of the Sierra 18-8218 Transom Seal Kit are 0.39 x 0.39 x 0.39 inches.

Is the Sierra 18-8218 genuine Sierra product or aftermarket? The 18-8218 is a Sierra-branded transom seal kit manufactured under the Sierra name for marine sterndrive service.

What application is this seal kit designed for? This kit is categorized for Mercruiser bellows applications, addressing the sealing components in the transom assembly on Mercruiser sterndrive setups.

Why replace all the seals at once instead of one at a time? A transom seal kit like the 18-8218 bundles all the wear-prone seals in the assembly together so that a full reseal is done in a single service, since the seals typically age and fail together.

Does the 18-8218 kit include installation hardware? The dossier for the Sierra 18-8218 identifies it as a seal kit; specific included hardware beyond the seals themselves is not detailed.

What is the UPC for the Sierra 18-8218 Transom Seal Kit? The UPC for the Sierra 18-8218 Transom Seal Kit is 808282305291.