Abstract: There is disclosed an automatic control system for limiting the operating temperature of a diesel engine having a pressurized intake manifold such as a turbocharged diesel engine. The system includes a pyrometer to sense the exhaust gas temperature from the engine and generate a signal therefrom, a temperature controller having an adjustable, maximum set point temperature to receive the signal from the pyrometer and to generate a control signal which is applied to a control valve in the manifold pressure line which applies manifold pressure to a pressure cell such as an aneroid unit that proportionally controls the position of the rack of the fuel supply. The control valve vents the manifold pressure line to the atmosphere and reduces the pressure on the aneroid unit to reposition the fuel rack in response to a sensed exhaust gas temperature which exceeds the preselected maximum set point temperature.

Abstract: There is disclosed automatic means for limiting the operating temperature of an internal combustion engine that includes a pyrometer to sense the exhaust gas temperature from the engine and generate a signal therefrom, a temperature controller having an adjustable, maximum set point temperature to receive the signal from the pyrometer and to generate a control signal which is applied to a control valve in the fuel system to the engine or to electromechanical means to limit the supply of fuel or governor control in response to a sensed exhaust gas temperature which exceeds the preselected, maximum set point temperature. The invention can be particularly applied to a diesel engine by installing a flow control valve in the diesel engine fuel system operative to cycle the valve when the exhaust gas temperature exceeds the preselected maximum, set point temperature.