Between 1923 and 1925 they were rebuilt with superheaters, and between 1927 and 1931, seventeen were transferred to the Fushun Coal Mine.

Between 1933 and 1936, fifteen were transferred to the Manchukuo National Railway where they were designated Sorina class (ソリナ), and between 1934 and 1936, Mantetsu assigned some to work on the North Chosen Line.

With the introduction of the final new classification scheme, the Mantetsu Sorii and Manchukuo National Sorina classes were unified as the Sorii class, with the Mantetsu engines numbered 1–9, and the Manchukuo National units becoming numbers 501–515.

After the end of the Pacific War, 23 Sorii class locomotives remained on the rosters of Mantetsu and Manchukuo National, with the other 18 thought to have been scrapped or transferred to other railways, including the North China Transportation Company.

After the establishment of the People's Republic of China, these locomotives were designated class MK1.