This workshop service repair manual covers the YANMAR 4BY2 and 6BY2 models within the BY Series of marine engines. Engineered for reliable marine propulsion, these inboard diesel engines are designed to deliver robust performance. YANMAR Marine is recognized for its commitment to quality and durability in marine applications, ensuring these engines are a dependable choice for various maritime needs.

This comprehensive English-language manual provides essential information for maintaining and repairing your YANMAR marine engine. It includes detailed repair and service procedures, troubleshooting guides, and technical specifications necessary for optimal engine performance. Whether you are an owner, a professional mechanic, or a technician, this manual serves as an indispensable resource for understanding, servicing, and ensuring the longevity of your YANMAR 4BY2 or 6BY2 engine.