Major Repair and Replacement of CNG Parts

When a vehicle is involved in an accident or a fire causing damage to the fuel tank, the fuel tank must be replaced. If damage occurred to other parts of the fuel system, also replace those parts.

Any and all replacement parts (valves, fittings, tubing, etc.) of the CNG fuel system must be designed specifically for CNG automotive use and must be officially approved and rated for the pressures and conditions that pertain.

Install parts and components in accordance with the manufacturer's instructions.

Replace (do not repair) damaged fuel lines. When replacing fuel lines, install the lines securely in a protected location, or shield them from heat sources and from contact with unsecured objects. Before assembly, apply a natural gas-impervious pipe thread jointing material to all male pipe threads. Ensure that all lines and fittings are clear and free of cuttings, threading burrs, and scales, and that the ends of all lines are reamed. Protect lines passing through a panel by means of grommets or similar devices. Locate joints and connections so that they are accessible.

Do not use aluminum or copper pipe, tubing, or fittings between the fuel tank and the first-stage pressure regulator because of the high pressure involved.

Ensure that shutoff valves have a rated service pressure not less than the rated service pressure of the entire fuel supply system, and that they are capable of withstanding a hydrostatic test of at least four times the rated service pressure.