VERTICAL AXIS BASE 65W-45331-00-5B PAF25-04000008

Function and technical context

The vertical shaft base is a fundamental structural component in Yamaha F25 series outboard engines, responsible for supporting and correctly aligning the vertical drive shaft that connects the crankshaft to the propeller. This part is part of the transmission system and must maintain precise alignment to ensure efficient transfer of power from the engine to the boat's propulsion. Wear, corrosion or misalignment in this base causes abnormal vibration during navigation, reduced propulsion performance and, in advanced cases, progressive damage to bearings and adjacent seals.

When to replace this part?

The base of the vertical shaft requires inspection when abnormal vibrations are detected in the engine tail, rubbing noises or lateral movement of the shaft that is perceived when manipulating the propeller with the engine off. Although there is no fixed time interval, it is recommended that this part be inspected during each seasonal maintenance, especially on vessels operating in silty waters or corrosive environments. The preventive replacement of this base avoids breakdowns during navigation that require costly repairs in port or outside of it, in addition to preventing secondary damage to adjacent, higher-value components.

Equivalent manufacturer part numbers