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.

1. Relieve the CNG fuel system pressure. Refer to the Fuel Pressure Relief .

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.

2. Disconnect the negative battery cable.
3. Remove the fill plate bolts.



4. Remove the fill valve and plate from the tank cover.
5. Remove the fill valve nut (1).
6. Remove the fill valve plate (2).
7. Disconnect the fill line (3) from the fill valve and discard the O-ring face seal.

Tools Required

J 41416 Ultrasonic Leak Detector

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.

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.

1. Connect the fill line (3) to the fill valve using a new O-ring face seal. Lubricate the O-ring with petroleum jelly or equivalent.

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

2. Connect the negative battery cable.

Tighten
Tighten the bolt to 15 N·m (11 lb ft).

3. Start the vehicle and inspect for CNG fuel leaks at the fitting using the J 41416 Ultrasonic Leak Detector or an equivalent liquid leak detector.
4. Install the fill valve plate (2).

Important: Align the mounting holes of the fill plate and the tank cover before tightening the fill valve nut.

5. Install the fill valve nut (1).

Tighten
Tighten the nut to 41 N·m (30 lb ft).




6. Install the fill valve and the fill plate in the cover.
7. Install the fill plate bolts.

Tighten
Tighten the bolts to 12 N·m (108 lb in).