Rocker Arm Assembly: Service and Repair
REMOVAL - ROCKER ARMS AND SHAFT1. Remove the cylinder head cover(s). (Refer to ENGINE/CYLINDER HEAD/CYLINDER HEAD COVER(S) - REMOVAL)
NOTE: Rocker arm shaft bolts are captured to the shaft.
2. Loosen the rocker shaft bolts (Fig. 24), rotating one turn each, until all valve spring pressure is relieved.
3. Remove the rocker arms and shaft assembly (Fig. 24).
4. For rocker arm disassembly procedures, (Refer to - ENGINE/CYLINDER HEAD/ROCKER ARMS DISASSEMBLY).
DISASSEMBLY - ROCKER ARMS AND SHAFT
CAUTION: Do not attempt to drive the billeted bolt from the rocker shaft. This can damage the rocker arm retainer and bolt assembly.
1. Remove the rocker arm retainer and bolt by performing the following procedure:
a. Using adjustable pliers, grip the edges of the retainer (Fig. 25).
b. Apply an upward force with a slight rocking motion until the retainer disengages from shaft (Fig. 25).
2. Remove rocker arms (Fig. 26). Identify the component locations for reassembly in original locations.
ASSEMBLY - ROCKER ARMS AND SHAFT
1. Install rocker arms on the shaft (Fig. 26). Install in the original positions if re-used. Ensure the rocker shaft, all the retainers and washers are properly positioned and installed in the correct locations (Fig. 26).
2. Install rocker arms and shaft to the cylinder head. (Refer to - ENGINE/CYLINDER HEAD/ ROCKER ARMS INSTALLATION)
INSTALLATION ROCKER ARMS AND SHAFT
CAUTION: Ensure the longer shaft retaining bolt is installed in the proper location on the rocker shaft. (Refer to - ENGINE/CYLINDER HEAD/ROCKER ARMS - ASSEMBLY)
1. Position the rocker arm and shaft assemblies on the pedestal mounts.
CAUTION: Ensure all pushrods are properly located on the lifter and the rocker arm socket.
2. Align each rocker arm socket with each pushrod end.
CAUTION: The rocker arm shaft should be tightened down slowly, starting with the center bolts. Allow 20 minutes lifter bleed down time after installation of the rocker shafts before engine operation.
3. Slowly tighten rocker shaft bolts evenly until shaft is seated. Tighten bolts to 23 Nm (200 inch lbs.) (Fig. 27).
4. Install the cylinder head cover(s). (Refer to ENGINE/CYLINDER HEAD/CYLINDER HEAD COVER(S) - INSTALLATION)