Cummins ISX11.9 CM2250 – Service Manual 006-024   Fuel Supply Lines

Inspect all fuel supply lines and fittings. Look for cracks in the lines or leaking fittings.

WARNING  When using a steam cleaner, wear safety glasses or a face shield, as well as protective clothing. Hot steam can cause serious personal injury.

WARNING  Wear appropriate eye and face protection when using compressed air. Flying debris and dirt can cause personal injury.

CAUTION  Clean all fittings before disassembly. Dirt or contaminants can damage the fuel system.

Before servicing any fuel system components, (such as fuel lines, fuel pump, injectors, etc.) which would expose the fuel system or internal engine component to potential contaminants prior to disassembly, clean the fittings, mounting hardware, and the area around the component to be removed. Dirt or contaminants can be introduced into the fuel system and engine if the surrounding areas are not cleaned, resulting in damage to the fuel system and engine. Refer to Procedure 000-009 in Section 0.

It is important to cover, cap, or plug any openings as soon as possible when servicing the fuel system in order to prevent engine damage. Caps and plugs can be found in Clean Care Kit, Part Number 4919073.

WARNING  Batteries can emit explosive gases. To reduce the possibility of personal injury, always ventilate the compartment before servicing the batteries. To reduce the possibility of arcing, remove the negative (-) battery cable first and attach the negative (-) battery cable last.

• Disconnect the batteries. Refer to the OEM service manual.

Fuel supply lines connect at the following joints:

1. Fuel filter head to fuel lift pump inlet (if equipped with a fuel lift pump)
2. Fuel lift pump outlet to fuel filter head (if equipped with a fuel lift pump)
3. Fuel filter head to fuel pump gear pump inlet
4. Fuel gear pump outlet to fuel filter inlet
5. Fuel filter outlet to high pressure fuel pump
6. Fuel filter outlet to aftertreatment shutoff manifold.

Remove the capscrews from the p-clips, as necessary.

NOTE: To remove the fuel line from the fuel filter head to the fuel pump gear pump inlet, remove the fuel filter head. Refer to Procedure 006-017 in Section 6.

Remove the fuel supply lines.

Discard the sealing washers.

Inspect for burrs or debris on banjo bolts and metal connectors that can cause leaks.

Inspect the p-clips for damage.  Replace any damaged p-clips.

Attach the fuel supply line that connects the fuel filter head to the fuel pump gear pump inlet to the back of the fuel filter head.

Tighten the p-clip.

NOTE: Installation of the fuel lines connected to the fuel lift pump will be easier if installed prior to mounting the fuel filter head.

Install the fuel filter head. Refer to Procedure 006-017 in Section 6.

• Tighten the banjo fittings.

Loosely install the following fuel supply lines:

1. Fuel filter head to fuel lift pump inlet (if equipped with a fuel lift pump)
2. Fuel lift pump outlet to fuel filter head (if equipped with a fuel lift pump)
3. Fuel gear pump outlet to fuel filter inlet
4. Fuel filter outlet to high pressure fuel pump
5. Fuel filter outlet to aftertreatment shutoff manifold.

Tighten the p-clip and banjo fittings.

WARNING  Batteries can emit explosive gases. To reduce the possibility of personal injury, always ventilate the compartment before servicing the batteries. To reduce the possibility of arcing, remove the negative (-) battery cable first and attach the negative (-) battery cable last.

• Connect the batteries. Refer to the OEM service manual.
• Prime the fuel system. Refer to Procedure 005-234 in Section 5.
• Operate the engine and check for leaks.