New Unit Information 02.2004Unit functions HD 5/12Page 10 / 121 Retaining plate2 Pressure valve3 Retaining plug4 Non-return valve5 Spring6 Ball7 Cleaning agent hose connection8 Injector9 High-pressure connection10 Cylinder headCylinder head11 Connection bore (pump pressure)12 Connection bore (dynamic pressure)13 Screw plug14 Connection bore to pressure switch (onlyindicated here)15 Overflow valve16 Valve seat17 Water connection18 Suction valves19 Cylinder head screws20 Piston1 2 3 2 3 2 35671818934 8101117181920 131516 1412