This workshop manual covers the Volvo Penta AQ Series engines, including models AQ105A, AQ115A, AQ130A, AQ130B, AQ130C, AQ165A, AQ170A, AQ170B, and AQ170C. These engines, known for their reliability and robust engineering, are designed for marine applications and feature liquid-cooled, carbureted systems. The 4-cylinder variants range from 2.1 liters producing approximately 105-130 HP, while the 6-cylinder variants utilize 3.2 liters to generate approximately 165-170 HP. These engines are paired with a marine sterndrive transmission, providing efficient power for a variety of watercraft. This comprehensive workshop manual is written in English and provides detailed guidance for the maintenance and repair of your Volvo Penta AQ Series engine. It covers essential areas such as safety precautions, general and technical descriptions, reconditioning instructions for various engine components including the cylinder head and block, and specific procedures for the lubricating, fuel, cooling, and electrical systems. Additionally, the manual includes information on type designations, test running, and special tools, ensuring that owners, mechanics, and technicians have the necessary resources to maintain the reliability and safety of their marine sterndrive engines.