PIÑON ATTACK 688-45551-01

Function and technical context

The drive pinion is the drive gear of the transmission system in Yamaha outboard motors, responsible for directly transferring power from the crankshaft to the speed reduction system and, finally, to the propeller. This component acts on the gear train by multiplying the engine torque to provide the force necessary to propulsion the boat. Its correct operation is essential to maintain smooth acceleration, avoid vibrations in the transmission and prevent gear slippage, which could lead to loss of thrust or accelerated wear of the driven pinions that compromises navigation.

When to replace this part?

The drive sprocket should be inspected regularly at each seasonal check, especially after sailing in areas with sand or sediment that accelerate tooth wear. Symptoms of deterioration include rough or metallic gear noises during acceleration, difficulty shifting gears, or a noticeable reduction in the engine's response to inputs. Its preventive replacement is recommended if cracks, accelerated wear on the teeth or if sand has been removed from the crankcase during maintenance are detected, thus avoiding costly repairs at sea that leave the boat without propulsion.

Equivalent manufacturer part numbers