This service repair workshop manual covers a range of JLO single and twin-cylinder engines, including models such as the L-99, L-230, L-295, L-340, LR-340/2, LR-399/2, LR-440/2, and LS-600/2. While specific production years are not detailed, the manual is designed for a broad spectrum of JLO engines, reflecting the brand's commitment to reliable and durable power units. These engines are known for their robust engineering, making them suitable for various applications where dependable performance is paramount. This comprehensive English-language manual provides detailed, step-by-step instructions, accompanied by diagrams, illustrations, and pictures, to assist users with engine fundamentals, operating procedures, and maintenance. It covers essential topics including carburetors, ignition systems, exhaust systems, disassembly and assembly, recoil starting, timing, wiring diagrams, troubleshooting, and service items. Written by manufacturers and offering vehicle-specific information, this manual is an invaluable resource for individuals with basic mechanical skills to independent professionals, enabling significant cost savings on repairs and maintenance.