This manual covers the Mercury Mercruiser 4.3L MPI engine, designed for Alpha and Bravo sterndrive applications. This V6, 4.3-liter (262 cubic inches) Multi-Port Injection engine is engineered for robust performance and reliability. Its advanced fuel injection system ensures efficient operation, making it a dependable choice for various marine uses. The serial number range covered by this guide begins with 0M300000 and extends to all subsequent models. The purpose of this comprehensive service repair manual is to provide detailed, illustrated instructions for the maintenance, diagnosis, repair, and rebuilding of your Mercury Mercruiser 4.3L MPI engine. It includes extensive coverage of the engine's mechanical components, electrical system, fuel system, cooling system, exhaust system, and power steering. With step-by-step procedures and troubleshooting support, this guide is an essential resource for DIY enthusiasts, professional technicians, and workshops seeking to maintain the optimal performance and longevity of their marine propulsion system.