Warning: It is obligatory to follow the general safety regulations specifically for vehicles operated using natural gas. Relieve pressure on the system by slowly slackening one of the bolted nuts on the CNG high pressure line, or by opening the CNG discharge connection, in the version with a CNG discharge connection. Always release system pressure by slowly opening the closure cap on the CNG discharge connection or the bolted nut on the CNG connection. After assembly/repair work, the CNG system must always be checked for leaks before starting the vehicle up again.
Remove
- 1. Open bonnet.
- 2. Disconnect battery. • Disconnect earth cable from battery.
Note. Disconnecting the battery ensures that the CNG magnetic coils are free of voltage and the safety valves on the modules are closed.
- 3. Depressurise CNG low pressure side. • Release union nut (1) with open ring spanner (3) and extension (2), allow gas to escape. – Counterhold with open-ended wrench against CNG pressure-reducing valve.
- 4. Depressurise the CNG high pressure side, in the version with a CNG discharge connection. • Slowly open closure cap (1) of CNG discharge connection and allow gas to escape. • Close the closure cap (1) on the CNG discharge connection again.
- 5. Depressurise the CNG high pressure side, in the version without a CNG discharge connection. • Slowly open union nut (2) of CNG high pressure line on underbody and allow gas to escape – Counterhold with open-ended wrench against connector (1) • Reclose union nut (2) of CNG high pressure line on underbody – counterhold with open-ended wrench against connector (1). Bolting together again: tighten union nut hand-tight, then turn a further 1/4 turn. When bolting together for the first time: tighten the union nut hand-tight, then tighten a further 1+1/4 turn.
Install
- 6. Tighten union nut of the CNG low pressure line on the CNG pressure-reducing valve - tightening torque 25 Nm • Counterhold with open-ended wrench against CNG pressure-reducing valve.
- 7. Connect battery. • Connect ground cable to battery.
- 8. Program volatile memories.
- 9. Check CNG high and low pressure systems for leaks
- 10. Close bonnet.