To reduce smoke at the time of quick acceleration without using an electric system by providing first lever regulating mechanism so as to allow the oscillation of a first lever into a moving quantity increase position when a governor lever is in an idling position and to limit a regulating position on the torque up position side when the governor lever is in a high rotation position.

At the time of starting an engine, a governor lever 7 is set into an idling position, so that a regulating cam plate 30 is positioned in a position (st) corresponding to a start quantity increase position ST. A first lever 1a is pressed to the fuel quantity increase side R by a start spring 2, and a rack pin 5 can be positioned in the start quantity increase position ST. In the case of operating the governor lever 7 suddenly onto the high rotation side, the regulating position of the regulating cam plate 30 is changed according to the turning angle of the governor lever 7 so as to be in a regulating position close to a position (tu) corresponding to a torque up position TU. The first lever 1a is therefore prevented from being oscillated going over this regulating position.