Fuel Rail and Injectors Installation (LDK, LHU)

Special Tools

• EN-47909  Injector Bore and Sleeve Cleaning Kit
• EN-48896  HP Fuel Pump Installation Alignment Gauge

For equivalent regional tools, refer to Special Tools (LDK, LHU) .

Fig 1: Fuel Rail Bolt Tightening Sequence
Courtesy of GENERAL MOTORS COMPANY
1. Clean the injector bore in the cylinder head using the EN-47909  cleaning kit.
2. Install the fuel rail with injectors into the cylinder head evenly.
3. Hand tighten the 2 outer fuel rail bolts to seat the injector into the injector bores.
CAUTION:

Refer to Fastener Caution .

4. Start and hand tighten the remaining fuel rail bolts.
   1. Tighten the fuel rail bolts in sequence to 25 N.m (18 lb ft).
   2. Tighten the fuel rail bolts in sequence a second time to 25 N.m (18 lb ft).
Fig 2: Fuel Injector Noise Insulator
Courtesy of GENERAL MOTORS COMPANY
5. Install the fuel injector noise insulator (1).
6. Connect the electrical harness to the fuel rail harness connection.
Fig 3: Using Alignment Gage
Courtesy of GENERAL MOTORS COMPANY
NOTE:

The camshaft must be in the base circle position before the high pressure fuel pump is installed.

7. Use the EN-48896  alignment gauge (2) to ensure that the camshaft lobe is in the base circle position. At base circle position, the tool will be flush with the head (1).
Fig 4: High Pressure Fuel Pump Roller Lifter
Courtesy of GENERAL MOTORS COMPANY
8. Lubricate the high pressure fuel pump cylinder head bore with 5W30 engine oil.
NOTE:

Ensure that the high pressure fuel pump roller lifter is oriented properly, the camshaft is at base circle, and the number 1 piston is at top dead center (TDC) on the exhaust stroke. The distance from the mounting flange surface to the camshaft at base circle should be 52 mm (2.05 in).

9. Lubricate the high pressure fuel pump roller lifter (1) with 5W30 engine oil and install into the cylinder head bore.
Fig 5: High Pressure Fuel Pump And Bolts
Courtesy of GENERAL MOTORS COMPANY
10. Install a NEW high pressure fuel pump gasket (1).
11. Install a NEW high pressure fuel pump O-ring (2).
NOTE:

Ensure the plastic bolt retainers are installed in the high pressure fuel pump mounting holes before installing.

12. Install the high pressure fuel pump (3).
13. Start and hand-tighten the high pressure fuel pump bolts evenly.
CAUTION:

Alternately hand-tighten the fuel pump bolts one turn at a time until the pump is fully seated. Trying to draw down the pump without even side-to-side tightening may result in pump plunger damage.

14. Tighten the high pressure fuel pump bolts evenly to 15 N.m (11 lb ft).
Fig 6: High Pressure Fuel Line
Courtesy of GENERAL MOTORS COMPANY
15. Install and hand-tighten both ends of the NEW high pressure fuel line (1).
16. Tighten the high pressure fuel line fitting nuts to 30 N.m (22 lb ft).