Engine Controls - 6.0L - Alternative Fuels (Introduction): Overhaul Chevrolet Silverado 3500

Disassembly Procedure

Use the following procedure if any HPR fittings require replacement

1. Remove the coolant fittings (2, 5).
2. Remove the pressure relief device (3).
3. Remove the fuel outlet fitting (4).
4. Remove the filter spring (4).
5. Remove the filter (3).
6. Remove the seal (2).

Assembly Procedure

1. Install the filter seal (2).
2. Install the filter (3).
3. Install the filter spring (4).
4. Install the fuel outlet fitting (4). Tighten: Tighten the fuel outlet fitting hand tight plus one to three turns as required to seal and properly align the fitting.
5. Install the pressure relief device (3). Tighten: Tighten the pressure relief device hand tight plus one to three turns as required to seal the fitting.
6. Install the coolant fittings (2, 5). Tighten: Tighten the coolant fittings hand tight plus one to three turns as required to seal and properly align the fitting.

1. Remove the crossover tube (3) rail retainer screws.
2. Remove the crossover tube.
3. Remove the CNG injectors (7) from the gasoline fuel injector adapters (6).
4. Separate the CNG fuel rail from the gasoline fuel rail.
5. Remove the fuel injector retaining clip.
6. Remove the injector from the fuel rail with a pulling and twisting motion.
7. Remove the fuel injector adaptor (6) from the gasoline fuel injector.
8. Repeat steps 5, 6 and 7 for the remaining fuel injectors.
9. Remove the CNG fuel rail pressure sensor or the temperature sensor hold down bolt (6).
10. Remove the sensor (2) from the fuel rail (4).
11. Remove and discard any remaining O-rings from the fuel rail.

1. Install the CNG fuel rail pressure sensor or the temperature sensor (2) into the fuel rail (4) with new O-rings (3). Lubricate the new O-rings with petroleum jelly.
2. Install the fuel rail pressure sensor or the temperature sensor hold down (5) and bolt (6). Tighten: Tighten the bolt to 3.8 N.m (34 lb in).
3. Install the CNG fuel injector (5) into the fuel rail (3, 4) with a new O-ring. Lubricate the new O-ring with petroleum jelly.
4. Install the fuel injector retainer clip.
5. Lubricate the new injector tip O-ring with clean engine oil.
6. Repeat steps 3, 4 and 5 for the remaining CNG fuel injectors.
7. Lubricate the new lower injector O-ring seals (4) with clean engine oil.
8. Install the new O-ring seals (4) on the spray tip end of each fuel injector (3).
9. Install the gasoline fuel injector into the fuel rail.
10. Install the fuel injector retainer clip.
11. Install the CNG fuel injector adapter to the end of the injector.
12. Repeat steps 7, 8, 9, 10 and 11 for the remaining injectors.
13. Assemble the CNG fuel rail (1, 4) injectors into the CNG fuel injector adapters (6).
14. Install new O-rings on the crossover tube (25).
15. Lubricate the new O-rings with clean engine oil.
16. Install the crossover tube (25) into the fuel rails (14, 15).
17. Loosely install the crossover tube fuel rail retainers (5, 21).

1. Remove the injector (5) hold down clip.
2. Remove the injector from the fuel rail with a pulling and twisting motion.
3. Repeat steps 1 and 2 for the remaining fuel injectors.
4. Remove the fuel rail pressure or temperature sensor hold down bolt (6).
5. Remove the sensor (2) from the fuel rail (4) with a pulling and twisting motion.
6. Remove and discard any remaining O-rings from the fuel rail.

1. Install the fuel rail pressure or temperature sensor (2) into the fuel rail (4) using new O-rings (3). Lubricate the new O-rings with petroleum jelly.
2. Install the fuel rail pressure or temperature sensor hold down (5) and bolt (6). Tighten: Tighten the bolt to 3.8 N.m (34 lb in).
3. Install the fuel injector (5) into the fuel rail (3, 4) using a new O-ring. Lubricate the new O-ring with petroleum jelly.
4. Install the fuel injector retainer clip.
5. Lubricate the new injector tip O-ring with clean engine oil.
6. Repeat steps 3, 4 and 5 for the remaining fuel injectors.