BEARING 93306-20401 REC93306-204Y7

Function and technical context

This bearing is part of the transmission and shaft support system in Yamaha and Mercury marine engines, allowing smooth and controlled rotation of the propeller. It works under conditions of high radial and axial load, constantly subjected to vibrations and stresses derived from aquatic propulsion. Its wear or degradation directly affects the efficiency of the engine, increasing internal friction, generating abnormal noises in the stern area and compromising the alignment of the tail shaft, which can lead to water entering the stuffing box or secondary damage to adjacent bearings.

When to replace this part?

Typical wear symptoms for this bearing include clunking or humming noise from the drive shaft, excessive vibration while running, and lateral play detected when manually forcing the shaft into port. It is recommended to visually inspect the condition of the bearing during each seasonal maintenance, especially after crossings in rough sea conditions or after sailing with sand or suspended sediments. Replacing it preventively before collapse avoids critical situations far from port and protects more expensive components such as the tail shaft or the coupling flange.

Equivalent manufacturer part numbers