Fuel Lines

REMOVAL

CAUTION: Cleanliness cannot be overemphasized when handling or replacing diesel fuel system components. This especially includes the fuel injectors, high-pressure fuel lines and fuel injection pump. Very tight tolerances are used with these parts. Dirt contamination could cause rapid part wear and possible plugging of fuel injector nozzle tip holes. This in turn could lead to possible engine misfire. Always wash/clean any fuel system component thoroughly before disassembly and then air dry. Cap or cover any open part after disassembly. Before assembly, examine each part for dirt, grease or other contaminants and clean if necessary. When installing new parts, lubricate them with clean engine oil or clean diesel fuel only.

1. Disconnect both negative battery cables from both batteries. Cover and isolate ends of cables.
2. Thoroughly clean fuel lines at both the cylinder head and injection pump ends.
3. If removing fuel line at either # 1 or # 2 cylinder, the intake manifold air heater elements must first be removed from top of intake manifold. Refer to Intake Air Heater Removal/Installation for procedures.

Fig.16 Bracket - #6 Injector:

4. If removing fuel line at # 6 cylinder, a bracket (Fig. 16) is located above fuel line connection at cylinder head. Two bolts secure this bracket to rear of cylinder head. The upper bolt hole is slotted. Loosen (but do not remove) these 2 bracket bolts. Tilt bracket down to gain access to # 6 fuel line connection.

Fig.17 Fuel Injector Rail:

5. Remove necessary insulated fuel line support clamps (Fig. 17) and bracket bolts at intake manifold.
6. Place shop towels around fuel lines at fuel rail and injectors. If possible, do not allow fuel to drip down side of engine.

Fig.18 High Pressure Fuel Lines:

CAUTION: WHEN LOOSENING OR TIGHTENING HIGH-PRESSURE LINES ATTACHED TO A SEPARATE FITTING (Fig. 18), USE A BACK-UP WRENCH ON FITTING. DO NOT ALLOW FITTING TO ROTATE. DAMAGE TO BOTH FUEL LINE AND FITTING WILL RESULT.


7. Carefully remove each fuel line from engine. Note position of each while removing. Do not bend lines while removing.


INSTALLATION
All high-pressure fuel lines are of the same length and inside diameter. Correct high-pressure fuel line usage and installation is critical to smooth engine operation.

1. Position fuel line support clamp to fuel line. Install clamp nuts/bolts and tighten finger tight.
2. Position proper fuel line to proper injector on engine. Tighten fittings hand tight at both ends of line.
3. Tighten fuel lines at high pressure injector connector to 30 Nm (22 lb.ft.).
4. Tighten fuel lines at fuel rail to 30 Nm (22 lb.ft.).
5. Tighten clamp/support nuts and bolts.
6. Install engine lifting bracket and bolt. Tighten bolt to 77 Nm (56 lb.ft.).
7. If fuel line at either # 1 or # 2 cylinder has been replaced, install intake manifold air heater elements to top of intake manifold. Refer to Intake Air Heater Removal / Installation for procedures.
8. If fuel line at # 6 cylinder has been replaced, tilt metal bracket upward and tighten 2 bolts at rear of cylinder head.
9. Install remaining fuel line support clamps and bracket bolts at intake manifold.
10. Connect both negative battery cables to both batteries.
11. Prime fuel system. Refer to Fuel System Priming.
12. Check lines/fittings for leaks.