No Diesel fuel manifold inlet

[JAV9411]

When i push the primer to put fuel in the manifold inlet, there is no fuel comming in the manifold inlet, the valve is open but my hand gets really sore![img]. In de manifold inlet is also a brass screw what is that for? If I pump with the fuel pump handle where is the fuel comming? Must it also come in the manifold inlet! What I do, there is no fuel comming in de manifold inlet, so it's very very very diffucult to cold start! Help Help