To improve the operability and maintenance ability of an engine by making it possible to adjust the actuation quantity of an Angleich mechanism from the outside of a governor case even while the engine is operated in a mechanical governor provided with the Angleich mechanism.

In the mechanical governor wherein the control lever pivotally supported on a tension lever can be moved from a rated injection quantity position to an Angleich position comprising a given quantity is increased to the rated injection quantity position, an Angleich adjusting mechanism for adjusting the Angleich position through the control lever is mounted on the rated injection quantity adjusting mechanism capable of adjusting the rated injection quantity adjusting position of the control lever so as to be movable, and the adjustment end section of the Angleich adjusting mechanism is provided in the outer section of the governor case.