High Pressure Regulator: Removal
WARNING: This page is about a different car, the 2003 GMC Sierra and 2003 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
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. Caution The Compressed Natural Gas (CNG) system operates at pressures up to 3600 psi (24,820 kPa). Relieve the CNG fuel system pressure before servicing CNG fuel system components in order to reduce the risk of fire and personal injury.
WARNING:
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(s). Failure to follow these precautions may cause personal injury and/or damage to the vehicle or its components.
NOTE:
Combustible Gas Detector (J-45878) is required for this procedure. See Figure
.
- Release fuel pressure. See FUEL SYSTEM PRESSURE RELEASE . Disconnect the negative battery cable(s). Remove the CNG fuel tank cover. See FUEL TANK COVER . Clamp off coolant hoses using coolant hose pinch pliers. Remove hose clamps and hoses from the high pressure regulator coolant fittings. See Figure . Remove the fuel inlet line from the High Pressure Regulator (HPR). Remove the fuel outlet line from the HPR. Remove the HPR fuel inlet line fitting from the HPR. Capture the filter spring, filter and seal that are located behind the fuel inlet line fitting.
- Do not hold the HPR using the hex flange at the end of the HPR near the warning label. Place the HPR in a suitable holding device in order to keep the HPR from spinning in the bracket. Remove the HPR mounting nut. Remove the HPR from the mounting bracket.
- To disassemble for replacement, place the HPR in a suitable holding device in order to keep the HPR from moving. Remove the coolant hose fittings. Remove the Pressure Relief Device (PRD). Remove the fuel outlet fitting.
- Connect the fuel outlet line to the outlet line fitting using a NEW "O" ring. Lubricate "O" ring with petroleum jelly before installation. Tighten the fuel outlet line fitting.