The DF design was based on a 1958 built prototype, the Julong, which was essentially a Soviet TE3 and was built with Soviet technical assistance.
The DF used a 10-cylinder opposed piston engine of type 10E207.
This was a copy of the Soviet 2D100 design, itself a copy of the Fairbanks Morse 38D8 ¾. Like the TE3s, the DFs were designed to be used in pairs, back to back, but appear to have spent most of their lives working singly, hardly a problem when there were wyes everywhere to turn steam locomotives.

DF and DF3 were used in many parts of China but by the late 1980s more modern diesels, such as the DF4B, had ousted them from primary routes.
Some hung on in CNR service until the mid 1990s but few, if any, made it beyond the millennium.
A number of redundant locos were bought by industrial and local railway operators, including the Heihe Local Railway in northern Heilongjiang.
Heihe's had finished by 2008 and it's highly unlikely that any remain in service.
The DF design was based on a 1958 built prototype, the Julong, which was essentially a Soviet TE3 and was built with Soviet technical assistance. The DF used a 10-cylinder opposed piston engine of type 10E207. This was a copy of the Soviet 2D100 design, itself a copy of the Fairbanks Morse 38D8 ¾. Like the TE3s, the DFs were designed to be used in pairs, back to back, but appear to have spent most of their lives working singly, hardly a problem when there were wyes everywhere to turn steam locomotives.
DF and DF3 were used in many parts of China but by the late 1980s more modern diesels, such as the DF4B, had ousted them from primary routes. Some hung on in CNR service until the mid 1990s but few, if any, made it beyond the millennium. A number of redundant locos were bought by industrial and local railway operators, including the Heihe Local Railway in northern Heilongjiang. Heihe's had finished by 2008 and it's highly unlikely that any remain in service.
China Railway DF