This marine service manual covers Volvo Penta MD21A, MD32A, AQD21A, and AQD32A internal marine diesel engines. Designed for optimal performance and reliability, these engines are engineered for demanding marine applications. This manual provides comprehensive information to ensure your engine operates at its peak efficiency and longevity. This Full Service & Repair Manual is an essential resource for owners, mechanics, and technicians. It details all repairs, servicing, and troubleshooting procedures with hundreds of pages featuring detailed photos, diagrams, and step-by-step instructions. The manual also includes highly detailed exploded diagrams, making it an indispensable tool for maintaining and repairing your Volvo Penta marine diesel engine.