This workshop manual provides information on servicing the 03-M-E3B, 03-M-DI-E3B, and 03-M-E3BG series diesel engines, including specifications, dimensions, and wiring diagrams. It contains four parts: Information, General, Mechanism, and Servicing. The Information section includes specifications, dimensions, and wiring diagrams. The General section covers engine identification, maintenance, and special tools. The Mechanism section describes the engine structure and function. The Servicing section includes troubleshooting, specifications, torques, and repair procedures.