Antique International cub cadet mower - (Anderson in Joplin, MO

This is what they call the original cub cadet lawn mower, according to the serial number it is a 1961 model.
Everything works, it smokes for a minute or two until it warms up
then it doesn't smoke anymore. I don't have the original seat, The motor had been changed by the original owner it is a Kohler
K181 motor. The original motor would have b