Installation Procedure
- Use the EN-48896 alignment gauge to ensure that the camshaft lobe is in the base circle position. At base circle the tool will be flush with the head.
- Lubricate the high pressure fuel pump cylinder head bore and roller lifter with camshaft prelube GM P/N 12345501 (Canadian P/N 992704) or equivalent.
- Install the high pressure fuel pump roller lifter (5).
- Install a NEW high pressure fuel pump O-ring (3).
- Position the NEW high pressure fuel pump gasket (4) and bolts (1) to the fuel pump.
- Install the high pressure fuel pump (2). Force will be required while hand tightening the bolts.
- Tighten the high pressure fuel pump retaining bolts to 15 N.m (11 lb ft).
- Ensure the high pressure fuel pump and fuel rail fittings are clean prior to assembly.
- Install a NEW high pressure fuel pipe. Refer to Fuel Feed Intermediate Pipe Replacement (LLT) .
- Install a NEW fuel feed pipe to the high pressure fuel pump. Refer to Fuel Feed Pipe Replacement .
- Connect the high pressure fuel pump wiring harness.
- Install the thermostat housing. Refer to Engine Coolant Thermostat Housing Replacement .
- Install the fuel tank cap.
- Inspect for leaks using the following procedure:
- Turn ON the ignition, with the engine OFF for 2 seconds.
- Turn OFF the ignition, for 10 seconds.
- Turn ON the ignition, with the engine OFF.
- Inspect for fuel leaks.
- Install the pressure relief cap to the fuel feed pipe.
NOTE:
The camshaft must be in the base circle position before the high pressure fuel pump is installed.
NOTE:
The high pressure fuel pump gasket has a retaining feature to hold the pump retaining bolts in place.
NOTE:
Lubricate the NEW O-ring seals with clean engine oil.
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.
CAUTION:
Refer to Fastener Caution .
NOTE:
If a fuel leak occurs at the fuel rail, the fuel rail will need to be replaced.