Fuel injection pump

A fuel injection pump for internal combustion engines having an adjusting device for an injection onset and having a suction chamber that is connected to a pre-supply pump, a fuel supply pressure operative in the suction chamber is controllable as a function of rpm and actuates the injection onset adjusting device by means of a pressure control valve (1) secured to said suction chamber, the pressure control valve includes a control piston (3) which is acted upon by the suction chamber pressure counter to the restoring force of a spring (5) accommodated in a spring chamber, said control piston (3) is provided with a control edge for controlling an outflow of a portion of the supplied quantity of fuel from the suction chamber, said spring chamber communicates with the suction chamber via a throttle (4) and also said spring chamber can be relieved via a pressure relief line (7) in which a pressure maintenance valve (8) is connected, a temperature dependent control device is provided by means of which the pressure maintenance function of said pressure maintenance valve can be rendered ineffective and the spring chamber of the control device can be relieved independently of the pressure maintenance function of the pressure maintenance valve, the pressure maintenance valve comprises a valve cylinder (13) in which a valve body (21) is disposed, said valve body includes a sealing face (22) which is urged by a compression spring to come to rest on a valve seat (20) surrounding the pressure relief line 97) entering at one face end of the valve cylinder (13), said valve body controls fuel flow from the pressure relief line to an opening to a continuing pressure relief line (37), the valve body (21) is disposed in the valve cylinder (13) either directly or indirectly with a tight sliding fit, and said opening to said continuing pressure relief line (37) is disposed between the valve seat (20), and the valve body (21) in the wall of the valve cylinder (13), said pressure relief line includes an outlet which is at least partly open when the valve closing element is in a closed position, the closing pressure of the pressure maintenance valve (8) is less than the pressure in the suction chamber at idling rpm of the engine, which suction chamber pressure is controlled by the pressure control valve (1) and the opening pressure of the pressure maintenance valve is greater than the closing pressure of the valve.