1 — Fuel line (163.113)/valve assembly (163.128)
2 — Bolts (TORX)
Y74 — Fuel Pressure Regulator Valve
1. Details of the installation of the fuel pressure regulator valve on diesel models are shown in the illustration, to which all references in the text refer.
2. On models 163.113 (612 series engine) remove the fuel line (see Section Removal and installation of fuel distribution line and injectors), on models 163.128 (628 series engine) remove the valve block (see Section Removal and installation of valve assembly on models 163.128).
Note: It is best to replace the regulator valve together with the fuel line/valve block.
3. If necessary, the pressure regulating valve (Y74) can be removed from the line/valve assembly clamped in a vice with soft jaws by unscrewing the mounting bolts (2).
4. Installation is carried out in the reverse order. Do not forget to replace the sealing elements.
5. Finally, start the engine and check the fuel system components for signs of developing leaks.