Production of the Ursus C-45 model began in 1946. Due to the need to begin production quickly, the Ursus company decided to copy the Lanz Bulldog D 9506. Examples of this German model were prevalent in the formerly German parts of post-war Poland, left behind following the expulsion of Germans at the end of World War II. Apart from its proximity and prevalence, the model also was advantageously high-powered relative to its simple construction and operation. Technical documentation for the C-45 was completed in July 1946 and was carried out under the guidance of Edward Habich. Under the designation LB-45, Habich built the first prototype in 1947, which was presented at the Labour Day parade in Warsaw on 1 May. Full production of the tractors was launched in September, with 130 units built by the end of 1947. The C-45 had a one-cylinder, two-stroke engine, with a maximum power of 33 kW and a cylinder capacity of 10,300 cc. The gearbox was 3-speed and the cylinder was placed horizontally. To start the engine, it was first heated by a blow lamp. Then, the steering wheel was removed, along with the column, and slid into one of the flywheels. By then turning the steering wheel, the engine was started. This process required physical strength and skill. At the beginning of its production life, the C-45 was manufactured with steel wheels. Modernising modifications were made to the tractor in later years, resulting in the improved C-451. The very first C-45, serial number 0001, worked 12,000 hours without intervening overhaul. Approximately 6,000 C-45 and C-451 tractors were exported to Brazil, China, and Korea.
C-451
The C-451 was the result of modifications made to the ageing C-45 in 1954. These changes included simplified operation, a more efficient fan, surface-hardened crankshaft, headlight, hydraulic lift, and starting gasoline fuel injection. A metal frame was fixed to the windscreen, rear fenders were fitted, and a canvas cab was added. The production of the C-451 in Warsaw was completed in 1959, with a total construction of 50,000 units. From 1960 to 1965, the C-451 was manufactured by Zakłady Mechaniczne in Gorzów Wielkopolski, after the technical documentation was passed to them.
