2008 6.6L Duramax – VALVE ROCKER ARM COVER REPLACEMENT – UPPER LEFT SIDE – Removal Procedure

1. Remove the intake manifold cover. Refer to Intake Manifold Cover Replacement.
2. Drain the cooling system. Refer to Cooling System Draining and Filling (Vac-N-Fill) or Cooling System Draining         and Filling (Static F ill).
3. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection (w/Single          Battery) or Battery Negative Cable Disconnection and Connection (w/Auxiliarv Battery) or Battery Negative Cable      Disconnection and Connection (w/Dual Batteries).
IMPORTANT: After removing the charged air cooler duct, cover the turbocharger opening with tape in order to prevent entry of objects.
4. Remove the charged air cooler inlet duct. Refer to Charge Air Cooler Inlet Pipe Replacement.

5. Remove the battery cable to generator nut.
6 . I f equipped, remove the battery cable to the auxiliary generator.
7. Remove the battery cable harness clip from the bracket.
8 . Remove the battery cable junction block bolt (1) from the power steering pump.
9. Move and secure the battery cables out o f the way.

10. Disconnect the fuel lines. Refer to Metal Collar Quick Connect Fitting Service
11. Remove the fuel hose bracket nut.

12. Disconnect the main engine electrical harness connectors. Lift up on the latches (1) in order to disconnect the              connectors.
13. Open the harness clip (2).
14. Remove the main engine electrical harness connectors.

15. Disconnect the turbocharger vane position sensor electrical connector (1).

17. Remove the main electrical connector harness bracket bolts (1).
18. Remove the main electrical connector harness bracket (2).
19. Remove the water outlet tube. Refer to Water Outlet Tube Replacement (L M M ).
20. Remove the auxiliary generator, if equipped. Refer to Auxiliary Generator Replacement (6.6L) .
21. Remove the positive crankcase ventilation (PC V ) hose/pipe. Refer to Positive Crankcase Ventilation                              Hose/Pipe/Tube Replacement.

22. Prior to removing the fuel injector pipes, use compressed air to blow any debris from between the injector line             and fittings. Wipe the fittings clean o f debris.
23. Spray lithium grease between the fuel injector line and fittings to assist in containing any debris during removal.         Refer to Sealers, Adhesives, and Lubricants for the correct part number.

24. Remove the left fuel injector pipes.

25. Remove the upper valve rocker arm cover bolts.
26. Remove the upper valve rocker arm cover.
27. Remove the upper valve rocker arm cover gasket.
28. Inspect the upper valve rocker arm cover gasket for damage, replace i f necessary. Otherwise reuse the old gasket.

29. I f required, clean and inspect the upper valve rocker arm cover. Refer to Valve Rocker Arm Cover Cleaning and          Inspection – Upper .