A fuel injection pump for internal combustion engines having an electromagnetic final control element, which in order to adjust the end or onset of injection engages a control slide, located in the pump interior. Via a control shaft, the final control element chamber is hermetically sealed off from the pump interior in order to keep water contained in the fuel from reaching current-carrying parts of the final control element. As a result, fluid communication exists only via the bearing gap of the slide bearing of the control shaft and the bearing gap functions as a throttle. The throttle forms a water separator, which further reduces the concentration of water in the already small quantity of fuel reaching the final control element chamber through the throttle.