This manual covers the Massey Harris 101 Senior and 102 Senior tractors, produced in the late 1940s and early 1950s. These models were integral to Massey Harris's agricultural machinery line, offering reliable power for a variety of farming tasks. They competed with other major manufacturers of the era, providing farmers with essential tools for cultivation and fieldwork. The tractors typically featured gasoline or kerosene engines, manual transmissions, and were designed for moderate drawbar pull, reflecting the robust engineering and practical utility that characterized Massey Harris products.

This comprehensive parts manual, identified by code R277A, is designed to assist owners, mechanics, and technicians in maintaining and repairing the Massey Harris 101 Senior and 102 Senior tractors. It provides detailed exploded diagrams and part numbers for all major systems, including the engine, fuel, ignition, cooling, transmission, drive axle, steering, brakes, electrical, hydraulics, chassis, and operator controls. The manual's primary focus is on accurate parts identification and procurement, offering the fundamental data necessary for ordering original equipment manufacturer (OEM) replacement parts, thereby supporting the longevity and operational integrity of these classic agricultural machines.