A centrifugal governor ensures a positive engine starting operation as well as a smoke control in the low engine speed range and a usual fuel injection control responsive to an increase in engine speed. A control rod with a rack is operatively connected with a floating lever through a spring biased piston and cylinder assembly, so that the control rod can be freely moved to its maximum fuel injection position during engine starting without being effected by a smoke limiter, which may be associated with the governor for a smoke control purpose. A unique lever mechanism is operable to move the control rod to the maximum fuel injection position during engine starting but, after a predetermined engine speed is reached, yields to a movement of the control rod in a fuel decreasing direction caused by the floating lever through the piston and cylinder assembly.