This workshop service manual covers the Yanmar SY Series marine engines, including models 6SY-STP2, 6SY655, 6SY700, 6SY750, and 8SY-STP. Yanmar is recognized for its commitment to engineering quality and reliability in marine propulsion. This manual is designed to provide comprehensive support for the maintenance, repair, and service of these robust marine engines, ensuring their optimal performance and longevity in demanding maritime environments. The purpose of this 280-page English-language manual is to serve as an authoritative resource for owners, technicians, and mechanics. It offers detailed technical information, step-by-step instructions, and visual aids such as diagrams, exploded views, drawings, and photos for a wide range of maintenance topics, including periodic maintenance, engine systems, fuel and cooling systems, lubrication, turbochargers, electrical components, and troubleshooting. Its searchable and bookmarked format facilitates efficient access to critical information, enhancing the ease and accuracy of service procedures.