Collar Harnesson

Function and technical context

The Arnesson TEN02516 collar is a fastening and guiding piece that is part of the transmission system for boats with Arneson Surface Drive type stern thrusters. Its main function is to maintain the alignment and tightness of the transmission shaft as it passes through the propeller structure, acting as a retaining element that prevents unwanted axial and radial displacements. Within the transmission assembly, this collar works under conditions of continuous vibration and exposure to the marine environment, so its structural integrity is decisive for the correct operation of the propeller. A damaged or broken collar can cause looseness in the shaft, abnormal vibrations while driving, water entering the internal components of the transmission and, in advanced cases, the complete disablement of the propeller in navigation.

When to replace this part?

The most common symptoms of wear or failure in an Arneson type transmission collar include unusual vibrations transmitted to the hull at any speed, metallic or clicking noises in the impeller area, and noticeable play in the shaft when manually inspected with the engine stopped. It is recommended to visually inspect the collar at each seasonal maintenance, paying attention to cracks, deformations or signs of material fatigue. Replacing it preventively in the event of any sign of deterioration avoids major breakdowns in the transmission assembly that can be very costly, especially if they occur during navigation.