This manual covers the Volvo Penta DP-A, DP-A1, and DP-A2 Duoprop sterndrive models. These units are engineered for reliable marine propulsion, featuring a robust design that integrates with various engine packages to deliver efficient power and precise control. The Duoprop system, with its forward, neutral, and reverse gears, is designed to optimize performance and maneuverability on the water, supported by a power trim and tilt system and hydraulic steering for enhanced operational ease. This comprehensive Factory Service Repair Manual, written in English, provides detailed guidance for all aspects of service, repair, troubleshooting, and diagnostics for the specified Volvo Penta sterndrive models. With hundreds of pages of information, it serves as an essential resource for owners, technicians, and mechanics. The manual includes critical data on lubrication, drive ratios, cooling systems, and scheduled maintenance intervals, empowering users to maintain their equipment effectively and ensure optimal performance and longevity.