RETAINER 26-8173971

Function and technical context

The 26-8173971 seal is a sealing component that seals the propeller shaft on Mercury, Mariner and Mercruiser outboard engines. It works in the propulsion system, specifically in the area where the drive shaft passes through the engine casing, preventing cooling water and lubricating oil from mixing or leaking to the outside. A defective seal allows salt water to enter the lubrication chamber, which causes internal corrosion, oxidation of metal parts and loss of oil viscosity, compromising the durability of the drive assembly.

When to replace this part?

This seal should be inspected regularly at each seasonal inspection, especially after navigation in contaminated salt or fresh water. Symptoms of deterioration include water dripping around the shaft, emulsion or cloudiness in the gearbox oil, and visible corrosion in the seal area. It is recommended to replace the seal preventively every 5-7 years or after 500-800 hours of operation, depending on navigation conditions. Replacing this component preventively is much more economical than repairing damage caused by water infiltration into the propulsion system.

Compatible engines

Compatible Mercury Mariner Engines

Equivalent manufacturer part numbers