Fuel injection system for combustion engines

In a fuel injection system for internal combustion engines, including a high-pressure part and a low-pressure part, in which in the high-pressure part, fuel from a fuel container is delivered to a high-pressure reservoir via a high-pressure pump and a high-pressure line, and injectors are supplied from the high-pressure reservoir via high-pressure supply lines, and in the low-pressure part the injectors communicate via injector return lines with a low-pressure reservoir, and in the low-pressure reservoir by means of a pressure holding valve, a pressure of ≦50 bar is maintained, and at a pressure in the low-pressure reservoir above the opening pressure of the pressure holding valve, the fuel is returned to the fuel container via a return line, the improvement comprising an overflow line connected between and communicating with the low pressure reservoir and the high-pressure line of the high-pressure part via an overflow valve connected in the overflow line.