Yamaha - Gear - Lower Unit Gear Component - 61B-45570-03-00

Overview

When a forward gear starts wearing out on these bigger Yamaha setups, you’ll feel it right away—slipping under load, hesitation when you put it in gear, or that rough engagement that just doesn’t feel right. This gear is a major player in how your outboard delivers power to the prop, especially on higher horsepower motors where everything is under more stress. It’s built to handle serious torque and keep things running smooth when everything’s dialed in. Replacing it during a rebuild is one of those moves that brings the whole lower unit back to life.

Key Features

• Primary Drive Gear Function – Handles forward power transfer from the drivetrain to the propeller under load.

• High Torque Capability – Built to withstand the demands of larger Yamaha outboards and heavy use.

• Precision Gear Tooth Cut – Designed for smooth meshing to reduce noise, vibration, and wear.

• OEM Construction Quality – Genuine Yamaha component engineered for long-term durability and proper gearcase alignment.

Engine & Boat Compatibility

Compatible with select Yamaha high-horsepower outboard lower units, commonly found in 225 HP and 250 HP V6 models. Always verify fitment using your engine model and service manual.

FAQ

Q: What are the signs this gear is going bad?
A: You’ll usually notice slipping in forward gear, grinding noises, or inconsistent acceleration under load.

Q: Is this a forward or reverse gear?
A: This is typically used as a forward drive gear in the lower unit assembly.

Q: Can I replace just this gear without a full rebuild?
A: Technically yes, but since it requires full lower unit teardown, it’s usually done during a rebuild.

Q: What causes this gear to wear out?
A: Low gear oil, water intrusion, or heavy impact damage are the most common causes.

Q: Will replacing this fix slipping under load?
A: If worn or damaged gear teeth are the issue, replacing it will usually restore proper engagement and power transfer.

• Supersessions
  61B-45570-02-00, 61B-45570-01-00, 61B-45570-00-00