fuel pump 11 feeds into the fuel line 7 a part of the flow stream of the fuel pump 11 travels through the connecting bore with the throttle 55 in the piston 53 and into the second chamber 59 causing the piston 53 to move toward the spring 63 counter to the force of the spring 63 fig5 shows the fourth exemplary embodiment in a second switched position the piston 53 is positioned so that the chamber 57 is hydraulically connected to both the connecting line 23 and the supply line 21 in this position the fuel pump 11 supplies fuel to both the fuel line 7 and the jet pumps 13 fig6 shows the third switched position of the 3 3 port directional control valve in this switched position the fuel pump 11 only feeds into the supply line 21 and not into the connecting line 23 this means that the entire output of the fuel pump 11 is fed to the jet pumps 13 fig6 a shows a modification in which a 3 2 port directional control valve is used in place of the 3 3 port directional control valve in this embodiment the line 23 is closed before the line 21 is opened so that the pump feeds only to line 21 in this fourth exemplary embodiment the fuel line 7 is filled as rapidly as possible and at the same time the jet pumps 13.