COLLARIN EJE USA 48 (MG)

Function and technical context

The shaft collar is a fundamental component of the transmission system in outboard engines and marine propulsion, whose mission is to retain and axially position the drive shaft, avoiding unwanted longitudinal displacements during operation. It works closely with the bearings and seals of the drive unit, ensuring that the shaft maintains its correct alignment under the thrust and traction loads generated by the propeller. A worn or cracked collar directly compromises the tightness of the assembly and can cause looseness in the shaft, abnormal vibrations and, in advanced cases, the entry of water into the interior of the conical group or transmission casing. The reference REC9148MG corresponds to the North American standard installation format (USA 48), with the MG suffix indicative of the specific material or finish used in its manufacture.

When to replace this part?

The most common symptoms of a damaged shaft collar include noticeable vibrations in the shaft or engine tail, metallic shaking noises at different operating speeds, and excessive axial play detected when manually moving the shaft with the engine stopped. It is recommended to inspect the collar at each seasonal inspection or each time the drive unit is operated to replace seals, bearings or the shaft itself; In intensive use vessels, the review should be carried out after 300-400 hours of navigation. Replacing this element preventively, taking advantage of any disassembly of the drive train, avoids major breakdowns at sea that involve the complete extraction of the propulsion group in difficult conditions.

Compatibility