The Allis-Chalmers B-112 Tractor, a product of a historically significant American manufacturer known for its distinctive orange machinery, represents a compact utility tractor designed for practical use. Belonging to a line of tractors intended for smaller farms, estates, and horticultural applications, the B-112 likely saw production in the mid to late 20th century. Its engineering emphasizes reliability and functionality, supporting a wide range of tasks through various factory and common attachments. This model is characterized by its robust construction and the inclusion of features such as a 3-speed transmission, a hydrostatic drive unit, and a Center PTO, making it a versatile and capable machine for its intended purpose. This comprehensive manual serves as an essential resource for owners, operators, mechanics, and restoration enthusiasts of the Allis-Chalmers B-112 Tractor. It consolidates information from Service Repair, Operator's, and Illustrated Parts Manuals into a single, detailed guide. The manual covers engine operation, maintenance, and diagnostics, alongside detailed procedures for steering, axles, clutch, brake systems, and the hydrostatic drive unit. It also includes extensive information on powertrain systems, electrical diagrams, and the installation and service of numerous attachments. With its searchable text, bookmarked chapters, and printable format, this manual provides in-depth coverage and clear instructions, ensuring the proper maintenance, repair, and safe operation of the tractor.