- Clean the sealing surfaces on the cylinder head and the valve rocker arm cover, so that the surfaces are free from oil and foreign material.
- Apply a 5-8 mm (3/16-5/16 in) bead of RTV sealant GM P/N 12346286 to the valve rocker arm covers, inboard of the bolt holes. The sealer must be wet to the touch, when the bolts are tightened.
- Install the valve rocker arm cover.
- Install the valve rocker arm cover bolts.
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.
Important: The RTV 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 fastened to the cylinder head, the RTV should flow on to both upper and lower levels of the step.
Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.
Tighten
Tighten the valve rocker arm cover bolts to 27 N·m (20 lb ft).
