This document pertains to the Westerbeke 65A Four Marine Diesel, a 4-stroke, water-cooled, diesel engine. It features a 4-cylinder inline configuration with a displacement of 3.31 liters. While specific power output figures are not detailed, the engine is designed for marine applications and is known for its robust construction and reliability. The manual covers various components and systems, including the cylinder head, valves, gearcase, oil pump, timing gears, camshaft, crankshaft, pistons, connecting rods, fuel system, governor system, glow plug system, cooling system, starter system, and alternator system. This comprehensive workshop and service repair manual in English provides detailed instructions and technical specifications essential for maintaining and repairing the Westerbeke 65A Four Marine Diesel. It includes procedures for engine overhaul, disassembly, and assembly, along with critical information such as tightening torques. The manual is equipped with detailed illustrations and step-by-step written instructions, making it an invaluable resource for both DIY enthusiasts and experienced mechanics. Troubleshooting guidance is also included to assist in diagnosing and resolving potential issues.