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Yamaha Lower Unit Assembly - 689-45300-17-4D
SKU: 689-45300-17-4D
$1,121.76 $1,138.65
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Description

This product has been superseded by: 689-45300-18-8D

Yamaha - Lower Unit Assembly - Gearcase Component - 689-45300-17-4D

Overview

The lower unit assembly is a critical component of your Yamaha outboard, responsible for transferring engine power to the propeller for efficient propulsion. Engineered with precision, this assembly ensures smooth gear engagement and consistent performance across a wide range of marine conditions. Its durable construction is designed to withstand corrosion, wear, and the demands of both freshwater and saltwater environments. Replacing a worn or damaged lower unit helps restore optimal handling, smooth shifting, and reliable engine operation.

Key Features

  • Complete Gearcase Assembly – Transfers engine power to the propeller for dependable propulsion.
  • Smooth Shifting Performance – Supports forward, neutral, and reverse gear engagement.
  • Durable Marine Construction – Built to resist corrosion and harsh environmental conditions.
  • OEM Yamaha Fitment – Designed to factory specifications for precise alignment and installation.

Engine & Boat Compatibility

Compatible with Yamaha outboards using this lower unit assembly within the drive system / gearcase assembly.

FAQ

Q: What does a lower unit assembly do?
A: It transfers engine power to the propeller and houses the gears for propulsion.

Q: What are signs the lower unit needs replacement?
A: Grinding noise, vibration, shifting issues, or water contamination in gear oil.

Q: Will replacing the lower unit improve performance?
A: Yes, especially if the current unit is worn or damaged.

Q: Is this a complete assembly?
A: Yes, it is a full gearcase assembly designed for replacement.

Q: Is installation difficult?
A: It typically requires mechanical experience and is often handled by technicians.

WARNING: This product can expose you to chemicals which are known to the State of California to cause cancer, birth defects or other reproductive harm. For more information go to P65Warnings.ca.gov.

Product Videos

Specs & Engine Application
  • Supersessions
    689-45300-16-4D, 689-45300-18-8D, 689-45300-18-8D

Reviews

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Yamaha Lower Unit Assembly - 689-45300-17-4D
Yamaha

Yamaha Lower Unit Assembly - 689-45300-17-4D

$1,121.76 $1,138.65

This product has been superseded by: 689-45300-18-8D

Yamaha - Lower Unit Assembly - Gearcase Component - 689-45300-17-4D

Overview

The lower unit assembly is a critical component of your Yamaha outboard, responsible for transferring engine power to the propeller for efficient propulsion. Engineered with precision, this assembly ensures smooth gear engagement and consistent performance across a wide range of marine conditions. Its durable construction is designed to withstand corrosion, wear, and the demands of both freshwater and saltwater environments. Replacing a worn or damaged lower unit helps restore optimal handling, smooth shifting, and reliable engine operation.

Key Features

Engine & Boat Compatibility

Compatible with Yamaha outboards using this lower unit assembly within the drive system / gearcase assembly.

FAQ

Q: What does a lower unit assembly do?
A: It transfers engine power to the propeller and houses the gears for propulsion.

Q: What are signs the lower unit needs replacement?
A: Grinding noise, vibration, shifting issues, or water contamination in gear oil.

Q: Will replacing the lower unit improve performance?
A: Yes, especially if the current unit is worn or damaged.

Q: Is this a complete assembly?
A: Yes, it is a full gearcase assembly designed for replacement.

Q: Is installation difficult?
A: It typically requires mechanical experience and is often handled by technicians.

WARNING: This product can expose you to chemicals which are known to the State of California to cause cancer, birth defects or other reproductive harm. For more information go to P65Warnings.ca.gov.

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