Fuel Tank Replacement Pickup with Type 2 Tank

1. If the tank is being removed in order to replace the high pressure lock-off (HPL) solenoid or for internal tank cleaning perform the High Pressure Lock-Off Solenoid Replacement instead of this procedure.
2. Relieve the CNG fuel system pressure. Refer to Fuel Pressure Relief .
3. If the tank is to be discarded or shipped it must be vented. Venting will damage the high pressure lock-off (HPL) solenoid. Refer to Fuel Tank Venting .

Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

4. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical in the C/K Pickup service manual.
5. Remove the fuel tank cover. Refer to Fuel Tank Cover Replacement .



6. Disconnect the high pressure lock-off (HPL) solenoid connectors (5,7).
7. Disconnect the fuel tank pressure (FTP) sensor connector (1).



8. Disconnect the high pressure regulator (HPR) fuel inlet line (3).



9. Remove the HPR fuel inlet fitting (6). Capture the filter spring (4), filter (3) and seal (2) that are located behind the inlet fitting.




Important: Do not hold the HPR using the HPR cover hex flange. As required wedge a wrench between the HPR and the tank frame in order to keep the HPR from spinning in the bracket.

10. Remove the HPR mounting nut (1).



11. Disconnect the fuel line (4) from the tee fitting (3).
12. Disconnect the tee fitting (3) from the HPL fitting (2).



13. Disconnect the fuel line clips (4) at the lower tank cover mounting bracket.
14. Disconnect the fuel line clips (3) at the tank frame (3).
15. Remove the fuel filter mounting bolts (1).
16. Remove the fuel filter and line assembly from the vehicle.



17. Disconnect the HPR coolant hoses from the lower tank cover mounting bracket retainers.
18. Remove the lower tank cover mounting bracket bolts (2).
19. Set aside the mounting bracket assembly in order to gain access to the tank strap retaining nuts.



20. Remove the upper tank cover mounting bracket bolts (3).
21. Remove the upper tank cover mounting bracket (1).



22. Remove the tank strap retaining nuts (5).
23. Remove the tank strap upper mounting clips (6) and pins (1).
24. Remove the tank straps from the vehicle.



25. Place the J 45529 (1) around the tank (2).
26. Connect the J 45529 (1) to a suitable lifting device and remove the tank from the vehicle.

1. Lower the fuel tank (2) into the tank mounting frame ensuring that the high pressure lock-off solenoid is properly oriented to the fuel line.



2. Place the straps (2) around the tank.
3. Install the tank strap upper mounting pins (1) and clips (6).

Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

4. Install the tank strap mounting nuts (5).

Tighten
Tighten the tank strap mounting bolts to 47 N·m (35 lb ft).




5. Install the upper tank cover mounting bracket (1) and bolts.

Tighten
Tighten the bolts to 8 N·m (71 lb in).




6. Slide the lower tank cover mounting bracket over the HPR and into position.
7. Install the lower tank cover mounting bracket and bolts (2).

Tighten
Tighten the bolts to 50 N·m (37 lb ft).

8. Attach the HPR coolant hoses to the lower tank cover mounting bracket retainers.




Important: Do not hold the HPR using the HPR cover hex flange. As required wedge a wrench between the HPR and the tank frame in order to keep the HPR from spinning in the bracket.

9. Install the HPR mounting nut (1).

Tighten
Tighten the nut to 54 N·m (40 lb ft).




10. Install the filter spring (4), filter (3) and seal (2) into the HPR inlet port.

Caution: Natural gas is stored under high pressure. If a leak occurs, the high pressure could cause a personal injury. In order to prevent Compressed Natural Gas (CNG) fuel leaks, always replace the CNG fuel system O-rings during service.

11. Install the HPR fuel inlet line fitting (6) with a new O-ring. Lubricate the O-ring with petroleum jelly.

Tighten
Tighten the fuel line fitting to 48 N·m (35 lb ft).




12. Install the fuel filter and line assembly.

Tighten
Tighten the bolts (1) to 27 N·m (20 lb ft).

13. Fasten the fuel line at the lower tank cover mounting bracket (4) and the tank strap (3).



14. Connect the fuel line (3) to the HPR fuel inlet fitting with a new O-ring face seal. Lubricate the O-ring face seal with petroleum jelly.

Tighten
Tighten the fitting to 37 N·m (27 lb ft).




15. Connect the tee (3) to the HPL fitting (2) with a new O-ring face seal. Lubricate the O-ring with petroleum jelly.

Tighten
Tighten the fitting to 37 N·m (27 lb ft).

16. Connect the fuel line (4) to the HPL fitting (3) with a new O-ring face seal. Lubricate the O-ring face seal with petroleum jelly.

Tighten
Tighten the fitting to 37 N·m (27 lb ft).




17. Connect the HPL solenoid connectors (5, 7).
18. Connect the FTP sensor connector (1).
19. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical in the C/K Pickup service manual.
20. Fill the CNG fuel system.
21. Start the engine and use the J 45878 in order to inspect for CNG fuel system leaks at each serviced fitting.
22. Install the fuel tank cover. Refer to Fuel Tank Cover Replacement .

Fuel Tank Replacement Cab/Chassis with Type 2 Tank

1. If the tank is being removed in order to replace the high pressure lock-off (HPL) solenoid or for internal tank cleaning perform the High Pressure Lock-Off Solenoid Replacement instead of this procedure.

Caution: Natural gas is highly flammable. In order to reduce the risk of fire and personal injury, keep sparks, flames, and smoking materials away from the vehicle while you perform the Compressed Natural Gas (CNG) fuel system service.

Caution: The Compressed Natural Gas (CNG) system operates at pressures up to 24820 kpa (3600 psi). Relieve the CNG fuel system pressure before servicing CNG fuel system components in order to reduce the risk of fire and personal injury.

2. Relieve the CNG fuel system pressure. Refer to Fuel Pressure Relief .
3. If the tank is to be discarded or shipped it must be vented. Venting will damage the high pressure lock-off (HPL) solenoid. Refer to Fuel Tank Venting .

Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

4. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical in the C/K Pickup service manual.
5. Remove the truck body as required on ZW9 equipped vehicles in order to gain access to the CNG fuel tank.



6. Disconnect the high pressure lock-off (HPL) solenoid connectors (5,7).
7. Disconnect the fuel tank pressure (FTP) sensor connector (1).



8. Disconnect the HPL fuel lines (1,3).



9. Remove the tank strap retaining nuts (2).



10. Remove the clips (4) and pins (5) from the tank strap mounting bracket.



11. Remove the tank straps (1).



12. Place the J 45529 (1) around the tank (2).
13. Connect the J 45529 (1) to a suitable lifting device and remove the tank from the vehicle.

1. Lower the fuel tank (2) into the tank mounting frame with the J 45529 .



2. Place the straps (1) around the tank.



3. Ensure that the high pressure lock-off solenoid is properly oriented to the fuel line fittings.
4. Install the tank strap mounting pins (5) and clips (4).

Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

5. Install the tank strap mounting nuts (7).

Tighten
Tighten the tank strap mounting bolts to 47 N·m (35 lb ft).

Caution: Natural gas is stored under high pressure. If a leak occurs, the high pressure could cause a personal injury. In order to prevent Compressed Natural Gas (CNG) fuel leaks, always replace the CNG fuel system O-rings during service.

6. Connect the fuel lines (1,3) to the HPL fittings with new O-ring face seals. Lubricate the O-ring face seals with petroleum jelly.

Tighten
Tighten the lines to 37 N·m (27 lb ft).




7. Connect the HPL solenoid connectors (5, 7).
8. Connect the FTP sensor connector (1).
9. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical in the C/K Pickup service manual.
10. Fill the CNG fuel system.
11. Start the engine and use the J 45878 in order to inspect for CNG fuel system leaks at each serviced fitting.
12. Install the truck body as required on ZW9 equipped vehicles.