This procedure applies to Single Overhead Camshaft (SOHC) engines only. On Dual Overhead Camshaft (DOHC) engines, the valves are actuated directly by the camshafts and no rocker arms are used.
- Before servicing the vehicle, refer to the Precautions section.
Remove or disconnect the following:
NOTEBe sure to note the installed positions of the rocker arm shaft assemblies before removal.
NOTEBe sure to keep the spacers and rocker arms in their original locations for installation.
Negative battery cable
Rocker arm shaft attaching fasteners, loosen them
Inspect the rocker arm for scoring, wear on the roller or damage to the rocker arm; replace any components showing damage. Check the location where the rocker arms mount to the shafts for wear or damage. Replace if damaged or worn. The rocker arm shaft is hollow and is used as a lubrication oil duct. Check the oil holes for clogs with a small piece of wire, and clean as required. Lubricate the rocker arms and spacers. Be sure to install in their original locations.
- Set the crankshaft sprocket to TDC by aligning the mark on the sprocket with the arrow on the oil pump housing, then back off to 3 notches before TDC.
- Install the rocker arm/hydraulic lash adjuster assembly making sure that the adjusters are at least partially full of oil. This is indicated by little or no plunger travel when the lash adjuster is depressed. If there is excessive plunger travel, submerge the rocker arm assembly into clean engine oil and pump the plunger until the lash adjuster travel is taken up. If travel is not reduced, replace the assembly. The hydraulic lash adjuster and rocker arm are serviced as an assembly.
Install or connect the following:
WARNINGWhen installing the intake rocker arm shaft assembly, be sure the plastic spacers do not interfere with the spark plug tubes. If the spacers do interfere, rotate them until they are at the proper angle. To avoid damaging the spark plug tubes, do not try to rotate the spacers by forcing the shaft down.
Rocker arm and shaft assemblies. Position the rocker arm shafts with the NOTCH FACING UP and toward the timing belt side of the engine.
- Install the rocker arm (valve) cover.
Connect the negative battery cable.