1. Remove the crankcase depression regulator (CDR) valve from the valve rocker arm cover.
2. Remove the turbocharger from the exhaust manifold (if servicing the right valve rocker arm cover only). Refer to Turbocharger Replacement .
3. Remove the lower intake manifold from the cylinder heads. Refer to Intake Manifold Replacement .



4. Remove the wiring harness from the right engine side of the engine if servicing the right valve rocker arm cover.



5. Remove the wiring harness from the left side of the engine if servicing the left valve rocker arm cover.
6. Remove the oil level indicator from the engine assembly (if serving the left valve rocker cover only). Refer to Oil Level Indicator and Tube Replacement .




Important: The heat shield between the cylinder head and the turbocharger must be remove to ensure the proper clearance to remove the fuel injector lines from the fuel injector nozzles.

7. Remove the heat shield between the turbocharger and the valve rocker arm cover (right side only).
8. Remove the fuel injector lines from the fuel injector nozzles. Refer to Fuel Injection Line Replacement in Engine Controls--6.5L-L65.



9. Remove the valve rocker arm cover bolts from the cylinder head.




Notice: Prying on the valve rocker arm cover may cause damage to the sealing surfaces. Use a block of wood against the side of the valve rocker arm cover and strike with a hammer in a sideways direction to shear the RTV sealant.

10. Remove the valve rocker arm cover from the cylinder head.
11. Remove all oil and grease from the sealing surface of the cylinder head (s).

Notice: Do not allow the RTV sealant to enter any blind threaded hole. RTV sealant that is allowed to enter a blind threaded hole can cause hydraulic lock of the fastener when the fastener is tightened. Hydraulic lock of a fastener can lead to damage to the fastener and/or the components. Hydraulic lock of a fastener can also prevent the proper clamping loads to be obtained when the fastener is tightened. Improper clamping loads can prevent proper sealing of the components allowing leakage to occur. Preventing proper fastener tightening can allow the components to loosen or separate leading to extensive engine damage.

1. Clean the sealing surface of the cylinder head.
2. Clean the sealing surface of the valve rocker arm cover.

Important: Apply a 5 to 8 mm (3/16 to 5/16 in) bead of RTV sealant to the valve rocker arm cover. The sealant should be applied such that it follows and overlaps the stepped ridge. This will distribute RTV on both the upper and lower levels of the step. When the valve rocker arm cover is fasten to the cylinder head, the RTV should flow on both the valve rocker arm cover and the cylinder sealing surfaces. The sealer must be wet to the touch when the bolts are tighten.

3. Apply the sealant GM P/N 12345739 to the valve rocker arm cover.
4. Install the valve rocker arm cover to the cylinder head. Refer to Valve Rocker Arm Cover Installation .
5. Install the fuel injection lines to the fuel injection pump and fuel injectors. Refer to Fuel Injection Line Replacement in Engine Controls-6.5L-65L.
6. Install the lower intake manifold on the cylinder heads. Refer to Intake Manifold Replacement .
7. Install the turbocharger on the exhaust manifold (if serving the right valve rocker arm cover only). Refer to Turbocharger Replacement .
8. Install the oil level indicator to the mounting bracket (if serving the left valve rocker arm cover only). Refer to Oil Level Indicator and Tube Replacement .



9. Install the wiring harness to the right engine side of the engine if servicing the right valve rocker arm cover.



10. Install the wiring harness to the left side of the engine if servicing the left valve rocker arm cover.



11. Install the heat shield between the turbocharger and the valve rocker arm cover (right side only).



12. Install the CDR valve to the valve rocker arm cover.