Yamaha - Starting Motor Gear Assembly Engine Starting Component 7CP-H1807-10-00. Overview. When you hit the key, this is one of the parts doing the real work behind the scenes. If the starting gear isn't engaging right, you'll hear it-grinding, slipping, or just nothing happening at all. I've seen engines that wouldn't turn over simply because this gear assembly was worn out. When it's in good shape, starts are quick, smooth, and consistent every time.. Key Features. • Reliable Gear Engagement - Transfers power from the starter motor to the engine for dependable starting.• Durable Gear Construction - Built to handle repeated starts and engine load without premature wear.• OEM Fit and Alignment - Matches factory specifications for proper engagement and smooth operation.• Consistent Start Performance - Helps eliminate slipping or grinding during engine startup.. Engine & Boat Compatibility. Designed for Yamaha outboard engines that utilize a gear assembly within the starting motor system