Fuel Receptacle (CNG): Service and Repair

Compressed Natural Gas Tank Filler Valve Receptacle Replacement

Special Tools

J-45878 - Combustible Gas Detector

For equivalent regional tools, refer to Special Tools Tools and Equipment.

Removal Procedure

Warning

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.

Warning

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.

1. Relieve the compressed natural gas (CNG) fuel system pressure. Refer to Compressed Natural Gas Fuel Pressure Relief (With CH-48027) Service and Repair.

Warning:
Refer to Battery Disconnect Warning Service Precautions.


2. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection Battery Negative Cable Disconnection and Connection.





3. Remove the fill line fitting from the fill valve.

4. Remove the fuel fill valve retaining bolts and reposition the pipe

5. Remove the 3 nuts retaining the fill valve plate.

6. Remove the fill valve and plate assembly.

7. Secure fill valve with a proper wrench and remove the fill valve jam nut.

8. Remove the fill valve from the mounting plate.

Installation Procedure

1. Install the fill valve into the mounting plate.

Caution:
Refer to Fastener Caution Fastener Caution.

2. Install the fill valve jam nut and tighten to 35 Nm (26 lb ft).





3. Reinstall the fill valve plate assembly with bolt support plate and 3 retaining nuts. Tighten the nuts to 10 Nm (89 lb in).

Warning

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.

4. Install the fill line fitting to the fill valve using a new O-ring. Lubricate the O-ring with petroleum jelly or equivalent before installation. Tighten the fill line fitting to 35 Nm (26 lb ft).

5. Turn on all Tank valves and install the fuel tank covers. Refer to Compressed Natural Gas Tank Cover Replacement - Aft Tank Compressed Natural Gas Tank Cover Replacement - Aft Tank , Compressed Natural Gas Tank Cover Replacement - Cargo Tank Compressed Natural Gas Tank Cover Replacement - Cargo Tank , and Compressed Natural Gas Tank Cover Replacement - Midship Tank Compressed Natural Gas Tank Cover Replacement - Midship Tank.

6. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection Battery Negative Cable Disconnection and Connection.

7. Prime the CNG fuel system by cycling the ignition ON and OFF several times.

8. Start the engine and use the J-45878 - detectoror equivalent in order to inspect for CNG fuel system leaks at each serviced fitting.