Abstract: A can filling machine having an improved mechanism to prevent overfill of the can. The machine includes a group of filling heads mounted on a rotatable turntable, and each head includes an outer tubular housing having an open upper end that communicates with a reservoir of the liquid, such as a beverage, which is intended to introduced into the can. A can is moved upwardly and is sealed against a cylindrical tulip that is mounted outwardly of the housing. A fill tube is mounted concentrically within the housing and the space between the fill tube and the housing defines an annular flow chamber for the liquid. Located concentrically within the fill tube is an air vent tube and the lower end of the air vent tube communicates with the can. The lower end of the fill tube carries a valve which is adapted to engage a valve seat on the lower end of the housing. Located in the lower end of the annular flow chamber is a stack of horizontal discs which are spaced vertically apart.