The fuel rail consists of four parts, Eight components in total where removed during the process, namely the fuel rail which is the pipe that delivers fuel to all the injectors, the
Fuel Pressure Regulator, the fuel pressure test port and six injectors. It is fixed on the intake manifold and supplies fuel to each cylinder trough its associated injectors.Fig 2 Flow of fuel from the fuel pump to the injectors The above description explain the flow of fuel from the fuel pump to the injectors as indicated in the following figure The function of the fuel pump, the position of the fuel rail and the kind of injectors used will be explained in detail in the later sections of this document. Fuel is pumped through fuel feed line to the inlet port of fuel rail pipe and it directs to fuel pressure regulator. Additional fuel not required in the engines passes through the pressure regulator assembly and out through the fuel rail outlet and into the fuel return line leading it back to the
Fuel Tank and the process continues. While working on the fuel rail assembly it is mandatory to ensure that no dirt or contaminants get into the fittings, especially when opening passages to the assemblies, suggestions such as capping of fittings or plugging holes during servicing of the units. This is done by bleading the fuel pressure from the system, then by using a spray type cleaner to clean the fuel rail assembly and connections but not with liquid solvent. Subsequently the fuel feed and return pipes of the fuel rail together with the vacuum line from the pressure regulator are disconnected and the electrical connectors of the injectors are unplugged. Subsequently, the fuel rail hold-down bolts are detached, so the rail can be pulled off with an equal pressure on each side. For installation, new O-rings must be installed on all replace parts, and, in particular, the injector O-rings should be lubricated with some drops of clean motor oil. The rail assembly is positioned on the manifold and injectors are seated with the hand and then the fuel rail hold-down bolts tightened to 22 ft. lb. (30 Nm). Last, the fuel-feed and the fuel-return pipes are inserted to the fuel rail tubes, the electrical connectors of the fuel-injectors are restored and the hose to vacuum-pressure regulator connected.