SMU - Revised Fuel System Cleaning Procedure

This bulletin is being issued to revise the Fuel System Cleaning (Fuel Tank Cleaning) procedure in the Engine Controls - 8.1L sub-section of the Service Manual. Please replace the current information in the Service Manual with the following information.

The following information has been updated within SI. If you are using a paper version of this Service Manual, please make a reference to this bulletin on the affected page.

Important: 

Caution: Before servicing any electrical component, the ignition key must be in the OFF or LOCK position and all electrical loads must be OFF, unless instructed otherwise in these procedures. If a tool or equipment could easily come in contact with a live exposed electrical terminal, also disconnect the negative battery cable. Failure to follow these precautions may cause personal injury and/or damage to the vehicle or its components.

1. Disconnect the negative battery cable.
2. Relieve the fuel system pressure. Refer to Fuel Pressure Relief Procedure.
3. Drain the fuel tank. Refer to Fuel Tank Draining Procedure.
4. Remove the fuel tank. Refer to Fuel Tank Replacement.
5. Remove the fuel sender assembly. Refer to Fuel Sender Assembly Replacement.
6. Inspect the fuel pump strainer. If the strainer is contaminated, replace the fuel pump.
7. Inspect the fuel pump inlet for dirt and debris. Replace the fuel pump if you find dirt or debris in the fuel pump inlet.
8. Locate a stand or fixture suitable to support the weight of the fuel tank and water.
9. Turn the fuel tank over so that the modular reservoir assembly opening is facing down.

Important: 

•	When flushing the fuel tank, handle the fuel and water mixture as a hazardous material. Handle the fuel and water mixture in accordance with all applicable local, state, and federal laws and regulations.

•	Do not drill any access or drain holes in the fuel tank.

10. Using a high pressure water spray-wand, spray all interior surfaces with clean/non-contaminated water. Be sure to spray all internal tank surfaces including fore and aft sections of tank behind baffles, while allowing water to drain out modular reservoir assembly opening. Perform each wash cycle for a minimum of 30 seconds using a minimum of 4 liters (1 gallon) of clean/non-contaminated water.
11. Using a high pressure air wand, dry all interior tank surfaces. Tank should be tipped accordingly to facilitate removal of water. Assure pressurized air does not contain any contaminants.
12. Repeat steps 10 and 11 for a total of 3 wash/dry cycles.
13. Hand dry tank surfaces with a white towel to confirm dryness and cleanliness. Use a non-metallic extension to push the towel beyond tank baffles.
14. Install the fuel sender assembly. Refer to Fuel Sender Assembly Replacement.
15. Install the fuel tank. Refer to Fuel Tank Replacement.
16. Refill the fuel tank.
17. Install the fuel filler cap.
18. Connect the negative battery cable.
19. Inspect for leaks:

19.1.

Turn ON the ignition for 2 seconds.

19.2.

Turn OFF the ignition for 10 seconds.

19.3.

Turn ON the ignition.

19.4.

Inspect for fuel leaks.