J/E THRUST WSHR 40-75HP OCTW - Solas

The thrust washer is mounted on the propshaft, between the lower unit and the propeller, and it may or may not have splines. It's an important component of a boat propeller's installation, because it fits the shaft in such a way that will not allow either itself or the propeller to move forward under thrust, thereby transferring thrust to the shaft and protecting the gear housing and its seal from contacting the rotating propeller. A matching taper on the propshaft and the washer is one effective design that stops a thrust washer from moving too far forward. The thrust washer also helps to keep the propeller centered on the shaft when the soft inner prop hub fails to do so under adverse high-torque conditions.