This comprehensive manual provides detailed information for operating and maintaining Lycoming O-320, IO-320, AIO-320, and LIO-320 aircraft engines. The manual covers a wide range of topics, including a thorough description of the engine, its specifications, and step-by-step operating instructions. You'll find guidance on performing periodic inspections and essential maintenance procedures, ensuring the longevity and optimal performance of your engine. The manual includes a valuable troubleshooting section to help you diagnose and address any issues that may arise. Furthermore, it covers installation and storage procedures, providing practical advice for handling your engine. With numerous tables for quick reference, this manual is an essential resource for anyone operating or maintaining Lycoming O-320 series engines.

The Lycoming O-320, IO-320, AIO-320, and LIO-320 are a family of four-cylinder, horizontally opposed, air-cooled aircraft engines produced by Lycoming Engines. These engines are renowned for their reliability, durability, and ease of maintenance, making them a popular choice for a wide range of general aviation aircraft. The O-320 series encompasses a variety of models with different power outputs, ranging from 150 to 180 horsepower. Each model features distinct characteristics in terms of their fuel injection systems, ignition systems, and accessories. The "O" in the designation stands for "opposed", referring to the engine's horizontally opposed cylinder configuration. The "I" denotes fuel injection, "A" signifies an alternator, and "L" represents a low-compression model. The O-320 series engines are known for their robust construction, benefiting from a cast-aluminum crankcase and forged steel crankshaft. They feature a dry sump lubrication system, which ensures consistent oil pressure regardless of flight maneuvers. The engines are equipped with a single magneto ignition system, providing reliable spark even in challenging conditions. The O-320's simplicity and straightforward design contribute to its ease of maintenance. A comprehensive operator's manual provides detailed instructions for routine checks, inspections, and repairs, making the engine suitable for both professional and private pilots. With its proven reliability and versatility, the Lycoming O-320 continues to power numerous aircraft across the globe, from single-engine trainers and recreational aircraft to utility and agricultural aircraft.