COLLARIN EJE USA 1-1/8" (MG)

Function and technical context

The shaft collar is an axial retaining component that is mounted on the boat's drive shaft to fix its longitudinal position and prevent unwanted movement during navigation. It works within the propellant transmission system, acting as a mechanical stop between the tail shaft and the horn or stopper elements, and ensuring that the propeller maintains its correct working position under the thrust and traction efforts generated by the propeller. A deteriorated, loose or fractured collar causes excessive axial play in the shaft, which results in vibrations, accelerated wear of the stern tube bearings and, in severe cases, loss of alignment of the drive assembly. This 1-1/8" shaft collar is manufactured according to the American dimensional standard (USA) and corresponds to the reference REC9140MG, being suitable for nautical installations that use that standardized shaft diameter.

When to replace this part?

The most common symptoms that indicate that the shaft collar needs to be checked or replaced are: perceptible longitudinal movement of the tail shaft when pushed manually, noises or knocking coming from the horn area during navigation, and abnormal vibration that is transmitted to the hull especially at low revolutions. It is recommended to inspect the collar at each docking or seasonal maintenance, checking that it does not present cracks, galvanic corrosion or play with respect to the shaft. Replacing the collar preventively when any sign of wear is detected prevents major damage to the horn and transmission assembly, repairs that may be unaffordable on the high seas.