This manual covers O-540, IO-540, and TIO-540 series aircraft engines. These opposed engines, with a displacement of 540 cubic inches, are available in naturally aspirated, fuel-injected, and turbocharged fuel-injected configurations, producing horsepower that varies by specific model variant. Designed for aviation applications, these engines are known for their robust engineering and reliability. This parts manual provides essential information for identifying and obtaining replacement components for these versatile powerplants.

The purpose of this parts manual is to provide comprehensive information for the O-540, IO-540, and TIO-540 engine series. It details replacement parts, enabling owners, mechanics, and technicians to accurately identify and procure necessary components for maintenance and repair. Its content is crucial for ensuring the continued operational integrity and performance of these aircraft engines.