This workshop service repair manual covers various Volvo Penta marine engine models, including the 280, 280-DP, 285, 290, 290-DP, SP-A, SP-C, DP-A, DP-B, and DP-C. Designed for inboard marine applications, these engines are known for their robust engineering and reliability. This manual provides comprehensive information for maintaining and repairing these units, ensuring their optimal performance and longevity in marine environments. The purpose of this English-language manual is to offer detailed guidance for service and repair. It includes step-by-step repair instructions, troubleshooting procedures, and technical specifications. Covered systems encompass engine mechanical and electrical components, emission control, fuel systems, clutch and transmission systems, driveshafts, steering, brakes, and body electrical and interior systems. Detailed illustrations, diagrams, and wiring schematics are provided to assist owners, mechanics, and technicians.