This comprehensive service and repair manual provides a detailed guide to maintaining and repairing your Yamaha 70hp and 90hp 2-stroke outboard motors manufactured between 1988 and 1994. It is the same manual used by professional mechanics and technicians, offering step-by-step instructions, highly detailed exploded diagrams, and clear illustrations to guide you through every repair procedure. This manual covers all aspects of servicing and troubleshooting, ensuring you have the necessary information to perform any repair or maintenance task confidently. With its in-depth coverage and clear presentation, this manual is an invaluable resource for anyone looking to keep their Yamaha outboard motor running smoothly.

The Yamaha 70hp and 90hp 2-stroke outboard motors, produced from 1988 to 1994, represent a significant chapter in the history of Yamaha's marine engine development. These powerful and reliable outboards were popular choices for a range of applications, from fishing and recreational boating to commercial work. Both models share a similar design, featuring a 701cc, two-cylinder, two-stroke engine with a single overhead camshaft (SOHC) and a reed valve induction system. They were renowned for their smooth operation, impressive torque, and relatively lightweight design. The 70hp version was a popular choice for smaller boats, offering excellent performance and fuel efficiency, while the 90hp model provided more power for larger vessels and heavier loads. Despite their age, these engines remain sought-after by boat owners due to their proven reliability and ease of maintenance. The robust construction and durable components ensure long-lasting performance, even with regular use. The 2-stroke design, while requiring a pre-mix of fuel and oil, provides a distinct power delivery that is unmatched by modern four-stroke engines. However, the 2-stroke design also means these engines are less environmentally friendly than their modern counterparts, and their fuel efficiency might not be as good as newer 4-stroke models. Regardless, the Yamaha 70hp and 90hp 2-stroke outboards continue to be a popular choice for boaters who value power, reliability, and a classic boating experience.