This manual covers the Yamaha 40 HP two-stroke, two-cylinder outboard marine engine, produced in 1982. This engine is designed for reliable performance in marine applications. While primarily for Yamaha models, it may also provide information applicable to some Mariner outboard engines from the same era. Its robust engineering ensures durability for various boating needs.

This document serves as a comprehensive guide for owners and technicians. It details essential maintenance procedures, troubleshooting steps for common issues, and provides critical technical specifications. Adhering to the guidelines within this manual will help ensure the longevity and optimal operation of your outboard engine, promoting safe and efficient use on the water.

This manual covers the Yamaha 40 HP two-stroke, two-cylinder outboard marine engine, produced in 1982. This engine is designed for reliable performance in marine applications. While primarily for Yamaha models, it may also provide information applicable to some Mariner outboard engines from the same era. Its robust engineering ensures durability for various boating needs.

This document serves as a comprehensive guide for owners and technicians. It details essential maintenance procedures, troubleshooting steps for common issues, and provides critical technical specifications. Adhering to the guidelines within this manual will help ensure the longevity and optimal operation of your outboard engine, promoting safe and efficient use on the water.