element 34 which is firmly connected with the drive shaft 17 and serves as a supply onset or angle indicator marking the holder pin 31 is subject to the force of a compression spring 36 which is supported in the guide sleeve 29 and thus keeps the drive shaft 17 of the injection pump 11 locked in the initially established rotary position in the desired manner the cross section of the groove 33 disposed on the end face is widened in trapezoidal form toward the protrusion 35 so that even when the apparatus housing 16 is displaced upward or downward by a few millimeters the groove 33 still fixes the protrusion 35 in position in a satisfactory manner in the illustrated embodiment the element 34 firmly connected with the drive shaft 17 is embodied by a sheet metal cage of a flyweight assembly 37 of the rpm governor 13 mounted on the injection pump 11 the protrusion 35 which serves as a supply onset marking and protrudes out of the surfce 38 of the sheet metal cage 34 comprises a tongue which is bent at right angles out of a cylindrical wall 39 of the sheet metal cage 34 the protrusion 35 has a rectangular end face 41 more clearly shown in fig5 which points radially outward from the drive shaft 17 and its longer edges extending perpendicular to the plane of the drawing extend parallel to the longitudinal axis of the drive shaft.