Yamaha - Clutch Dog Lower Unit Shifting Component 6L2-45631-00-00. Overview. When shifting starts getting rough or the motor won't stay in gear, the clutch dog is usually where the problem shows up. It's the part that actually locks the gears in place, so once it wears down, everything feels off. I've seen plenty of lower units brought back to life just by replacing this one piece. When it's right, you get that solid, clean engagement every time you shift.. Key Features. Positive Gear Engagement - Locks gears securely for reliable forward and reverse operation.. Hardened Metal Construction - Built to handle repeated shifting without premature wear.. Precision Machined Fit - Ensures proper alignment within the lower unit gear system.. Restores Shift Reliability - Helps eliminate slipping or popping out of gear.. High Wear Resistance - Designed to withstand constant contact under load.. Engine & Boat Compatibility. Designed for Yamaha outboard engines with compatible lower unit gear syst