Detailed Operation of the Governor

DIESEL ENGINE SPEED, DOE-HDBK-1018/1-93 Diesel Engine Fundamentals FUEL CONTROLS, AND PROTECTION Detailed Operation of the Governor With the engine operating, oil from the engine lubrication system is supplied to the governor pump gears, as illustrated in Figure 29. The pump gears raise the oil pressure to a value determined by the spring relief valve. The oil pressure is maintained in the annular space between the undercut portion of the pilot valve plunger and the bore in the pilot valve bushing. For any given speed setting, the spring speeder exerts a force that is opposed by the centrifugal force of the revolving flyweights. When the two forces are equal, the control land on the pilot valve plunger covers the lower ports in the pilot valve bushing. Figure 29 Cutaway of a Woodward Governor ME-01 Rev. 0 Page 36