COLLAR SHAFT 25mm.

Function and technical context

The 25 mm shaft collar is an axial positioning and retention element that acts directly on the boat's drive shaft, keeping it aligned and preventing unwanted longitudinal displacements during propeller operation. It works within the transmission and drive system, in the shaft passage area between the hull and the propeller, a point subjected to dynamic loads and constant vibrations typical of navigation. Its correct operation is essential to guarantee the tightness of the assembly and the efficiency in the transfer of engine torque to the propeller. If the collar deteriorates or loses its working position, looseness in the shaft, abnormal vibrations and, in severe cases, water entering the interior of the helmet through the horn may occur.

When to replace this part?

The most common symptoms that indicate wear or failure of a shaft collar are unusual vibrations in the shaft line at different revolutions, noticeable axial play when manually moving the shaft, and the appearance of water leaks in the horn or stuffing box area. It is recommended to inspect the collar at each docking or seasonal maintenance, checking the tightness, the absence of corrosion on the fixing screws and the condition of the piece as a whole. Replacing the collar preventively if there is any sign of wear prevents more costly damage to the shaft line and guarantees the safety of the boat while sailing.

Compatibility