KEY 90280-03M03

Function and technical context

The key is a critical fastening element in the power transmission systems of Yamaha engines, responsible for ensuring the connection between the shaft and its coupled components, preventing relative slippage under load. This part works inside the propulsion system, subjected to constant torque and vibration during engine operation. Its correct condition guarantees the efficient transfer of power from the crankshaft to the propeller or auxiliary systems, avoiding performance losses and cascading damage to other mechanical components.

When to replace this part?

The key requires inspection when abnormal vibration is detected in the drive shaft, mechanical knocking in the engine casing, or difficulty changing gears. Although it is not subject to accelerated wear like other moving parts, it is advisable to check its integrity during each seasonal maintenance, especially after intense navigation or in water with sediment. Preventively replacing this part during major overhauls avoids unpredictable failures on the high seas that would compromise the boat's maneuverability.

Equivalent manufacturer part numbers