Tools Required

J 45878 Combustible Gas Detector

1. Relieve the CNG fuel system pressure. Refer to Fuel Pressure Relief .
2. Lower the rear seat.
3. Loosen the lower vent hose clamp.
4. Pull the vent hose from the HPR.
5. Disconnect the HPR to the HPL fuel line from the HPR.



6. Remove the HPR mounting nut.



7. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information in the J Platform Service Manual.
8. Install hose pinching clamps on the coolant inlet and the outlet lines at the HPR.
9. Remove the coolant hoses from the HPR.



10. Disconnect the fuel outlet line (4) from the HPR.
11. Remove the HPR.

1. Connect the coolant inlet and outlet hoses to the HPR.
2. Remove the hose pinching clamps from the coolant inlet and outlet lines.
3. Position the HPR through the mounting hole.



4. Connect the HPR fuel outlet line (4) to the HPR using a new O-ring face seal. Lubricate the O-ring with petroleum jelly or the equivalent.

Tighten
Tighten the fuel line fitting to 24 N·m (18 lb ft).

5. Lower the vehicle.




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.

6. Install the mounting nut to the HPR.

Tighten
Tighten the HPR mounting nut to 55 N·m (41 lb ft).




7. Connect the HPL to HPR fuel line to the HPR using a new O-ring face seal. Lubricate the O-ring with petroleum jelly or the equivalent.

Tighten
Tighten the fuel line fitting to 24 N·m (18 lb ft).

8. Connect the HPL power electrical connector.
9. Start the engine. Inspect for CNG fuel leaks at each serviced fitting using the J 45878 .
10. Install the vent hose to the HPR.

Tighten
Tighten the clamp to 2 N·m (18 lb in).

11. Raise the rear seat.
12. Check the coolant level. Add coolant as needed. Refer to Cooling System Draining and Filling in Engine Cooling in the J Platform Service Manual.