The parts were taken from the building in Great Heck, near Selby, at some point between 4pm on Thursday and 9am yesterday.
The offenders are thought to have used a wheelbarrow to remove the parts from the farm building, and the missing items include a radiator, a starter motor and alternators from a Super WD6 tractor and a David Brown 30D model.
Pc Julia Allen, who is involved in the North Yorkshire Police investigation into the theft, said: “It is unknown how much the parts are worth but they are very rare and will be extremely difficult to replace.
“I am appealing to anyone who saw any suspicious activity in the area around the time of the theft or anyone who has been offered the parts for sale to get in touch with the police as soon as possible.”
Anyone with information about the theft is asked to contact Pc Allen or her colleagues based in Selby on North Yorkshire Police’s non-emergency number of 101 or via the Crimestoppers charity on 0800 555111.
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