COLLARIN EJE Ø 25mm STD (MG)

Function and technical context

The 25 mm shaft collar acts as a retention and axial positioning element for the transmission shaft in outboard motors and marine powertrains, preventing unwanted longitudinal movements that would compromise the alignment of the assembly. It works in the transmission and propulsion system, being located in the exit area of ​​the shaft towards the propeller, where the axial and radial loads are continuous during navigation. Its correct fastening guarantees that the engine torque is efficiently transmitted to the propeller without abnormal vibrations or loss of performance. A damaged collar or one with excessive play can cause shaft misalignment, accelerated wear of adjacent seals and bearings, and even water entering the motor body through the stuffing box.

When to replace this part?

The most common symptoms of wear on a shaft collar are noticeable vibrations in the tiller or transom while sailing, a dull metallic noise coming from the transmission group, and visible axial play when manually moving the propeller shaft. It is recommended that the collar be inspected during each seasonal maintenance—at least once a year—and replaced if there is any sign of looseness, galvanic corrosion, or ring deformation. Replacing it preventively along with the shaft seals and bearings avoids serious breakdowns in navigation and costly interventions in travelift or dock.

Compatibility