This manual provides comprehensive technical information for the 2011 engine series, covering various configurations including the F2L, F3L, F4L, F2M, F3M, F4M, BF3L, BF4L, BF3M, and BF4M models. Engineered for reliability and performance, the 2011 engine is a robust power unit designed for demanding applications. This factory service repair manual offers in-depth guidance, ensuring that owners and technicians can effectively maintain and repair these engines to factory standards. The scope of this manual encompasses all essential aspects of engine service and repair. It includes detailed sections on general information, specifications, safety regulations, operating procedures, and troubleshooting. Furthermore, it provides step-by-step repair instructions, test and adjustment data, tightening specifications, and information on commercial and special tools. With its clear diagrams, illustrations, and comprehensive troubleshooting guide, this manual empowers users to perform diagnostics and repairs efficiently, thereby reducing downtime and optimizing engine performance.