26-88397A1 Driveshaft Housing Upper Unit Seal Kit 88397A1 For Mercruiser Stern Drive Alpha One Gen II 26-88397A1 Sierra 18-2644 The 26-88397A1 Driveshaft Housing Upper Unit Seal Kit is designed for use with the upper unit of Mercruiser Stern Drive systems.This seal kit replaces worn factory seals that degrade over time due to exposure to water, salt, and mechanical.It includes all necessary components for a complete replacement such as the main seal, O-rings, and related parts that a watertight and oil-tight seal.This kit is compatible with Mercruiser Alpha One Gen II and Sierra 18-2644 models, providing a direct fit for these applications.The 88397A1 is equivalent to 26-88397A1 and refers to the same seal assembly.The upper unit in a stern drive system transfers power from the engine to the propeller and contains the driveshaft.Over time, seals can wear, allowing water ingress which may lead to internal corrosion, bearing damage, or lubricant loss.Replacing the seals helps maintain the integrity of the unit, supports performance, and may prevent more extensive repairs.Constructed from marine-grade materials, the kit resists corrosion and performs under varying temperature conditions.It is engineered to match the specifications of the , compatibility and function.The complete set of included components allows for a full service without sourcing individual parts.Installation is designed to align with standard procedures for the specified models.Proper fit helps minimize leaks and supports consistent.Regular maintenance using this seal kit contributes to the overall of the propulsion system.