Wallis had been purchased by Massey Harris in 1928 in order for Massey Harris to become a full line agricultural machinery company. Having a full line to offer farmers was thought to be an advantage at the time. This trend had been started in the early 1900s by IHC which, partially as a result of building and offering for sale every machine likely to be needed by a farmer, was very successful. Other machinery companies realized that they also needed to offer a fairly comprehensive line of machinery in order to keep their customers from going elsewhere to obtain some machine and in doing so, fall into the hands of a competing machinery company.
Wallis in 1928 was owned by the J.I.Case Plow Works which was separate from the Case Threshing Machine Company which was the company which built steam engines, Case tractors and Case threshing machines.
J.I. Case Plow Works by 1928 had been badly weakened by the competition from Fordson and Farmall tractors and the economic downturn of the early 1920s. Massey Harris purchased the company for $2,400,000. Massey Harris promptly turned around and sold the J.I. Case Plow Works name to Case Threshing Machine Company for $700,000. Case Threshing Machine changed their name to the J.I. Case Company at that time.
Massey Harris continued on selling the Wallis line of tractors under the Wallis name. In 1932 Massey Harris decided that the tractors needed some updating and a change from the Wallis name to Massey Harris. The designs were selling as well as possible in 1932, the height of the Great Depression and if Massey Harris could extract a few more years from the Wallis designs the company could avoid making a major outlay for design and development of new tractor designs at a time when money was very tight.
The update of the Wallis 20/30 saw the four cylinder engine’s rpm increase to 1200 rpm which gave a horsepower rating of 26/41. One could order either a kerosene or distillate fuelled engine. A three speed transmission was standard as were brakes on the rear wheels. The Model 25 was painted in Massey Harris’s dark green paint scheme.
Approximately 14,000 Model 25s were sold between 1933 and 1938. In 1938 the Model 25 was streamlined and painted red, however the mechanical details remained the same. Only about 1000 streamlined Model 25s were sold between 1938 and 1946 when production of the Model 25 was ended.
The Model 25’s production run was not bad for a tractor meant to be a stop gap until better conditions returned and money could be spent on a major design effort, but then Wallis roots meant that the basic design was in advance of the competition in many aspects. The frame was built out of a single piece of curved boiler plate which combined the crankcase, transmission case and frame into one piece resulting in a lighter yet stronger tractor. The engine used removable cylinder sleeves, hemispherical combustion chambers, an oil filter with replaceable filters and advanced materials for the time. The same basic transmission design of the 20/30 served the Model 25 and other Massey tractors finally ending with the Massey Harris 555.