Yamaha - Clutch,dog - 6L2-45631-00-00Yamaha Clutch Dog Lower Unit Shifting Component 6L2 45631 00 00 Overview When shifting starts getting rough or the motor wont stay in gear, the clutch dog is usually where the problem shows up. Its the part that actually locks the gears in place, so once it wears down, everything feels off. Ive seen plenty of lower units brought back to life just by replacing this one piece. When its right, you get that solid, clean engagement every time you shift.