How a Lower Units Works
How Gear Box Works The input shaft is driven from the engine or 'power head'. (This input shaft is called the driveshaft) The driveshaft has a gear connected to the bottom of it called the Pinion gear. The pinion gear is always in constant mesh with the forward and reverse gears. Whenever the motor is running, the pinion gear is rotating the forward and reverse gears. The Clutch Dog Between the forward and reverse gear there is the mechanism that selects gear. This is called the Clutch Dog. The Clutch Dog has an internal spline that is in constant mesh with the propeller shaft. Picture the Clutch Dog having a front and a back. At each end it has large, square teeth. When you select gear on the motor you move the Clutch Dog forwards and backwards along the propeller shaft. How Gear Box Works When the Clutch Dog is moved to select gear, it engages with the same sized square teeth on the gear that is being engaged. Remember that both ou