CM Transom Bellows Kit for Mercruiser Alpha One Gen 2 — 803099T1 Complete Seal & Gimbal Repair Kit

If you own a Mercruiser Alpha One Gen 2 sterndrive (1991 and up) and need to service leaking or worn transom components, this CM 803099T1 kit gathers the common failure parts into one package. It replaces OEM part numbers such as MerCruiser 30-803099T1 and compatible aftermarket references, and includes molded neoprene bellows, a gimbal bearing, intake hose, gasket set, and stainless steel clamps to restore sealing and function at the transom.

What parts are included in the 803099T1 kit and what do they do?

The kit bundles the pieces most often replaced during transom service to stop water intrusion and maintain steering/shift function. Each component is selected to match fit and material requirements for Alpha One Gen 2 sterndrives.

• U-joint bellow (816431A1) — protects the universal joint from water and debris.
• Shift cable bellow (74639) — seals the shift linkage at the transom.
• Exhaust bellow (18654A1) — prevents exhaust path leaks through the transom.
• Gimbal bearing (30-60792A4) — supports the drive shaft and maintains alignment.
• Water intake hose (3/4", 32-41725-33), gasket kit (27-94996T2), O-rings and stainless clamps — complete sealing and connection hardware.

Which boat models and serial ranges is this compatible with?

This CM kit is designed to fit Mercruiser Alpha One Gen II sterndrives across multiple model years and serial number ranges. Check your drive serial to confirm exact compatibility before ordering.

• Alpha One Gen 2 models, 1998 and later maintenance fits.
• 1996–1997 drives within serial 0F680000 through 0K999999.
• 1991–1995 drives within serial 0D469859 through 0F679999.

How do materials and components resist marine conditions?

Critical sealing parts are molded from CR neoprene for saltwater and UV resistance, while fasteners use stainless steel to reduce corrosion. Gaskets and O-rings are marine-grade for durability under repeated immersion and movement.

• Bellows: CR neoprene for abrasion and salt tolerance.
• Clips and clamps: stainless steel to minimize rusting.
• Gaskets/O-rings: marine engine-grade compounds for reliable sealing.
• Gimbal bearing: designed to withstand thrust and rotational loads.

What should I know about installation and maintenance?

Installation typically requires removing the outdrive for safe access, inspecting mating surfaces, and replacing worn fasteners and seals. Follow torque specs and alignment steps from your service manual to ensure proper driveline geometry.

• Inspect the transom housing and drive mounting surfaces for corrosion before install.
• Lubricate bearing surfaces and use correct marine sealants where specified.
• Replace clamps and O-rings included in the kit to ensure tight seals.
• Perform a sea trial after reassembly to verify no leaks and correct shifting.

Who is this for: The CM 803099T1 Transom Bellows Kit is aimed at boat owners, marine technicians, and DIY mechanics who maintain Mercruiser Alpha One Gen 2 sterndrives from 1991 onward. It suits anyone preparing for transom service, addressing bellows or gimbal bearing wear, or rebuilding a used outdrive to restore reliable sealing and driveline support.