To remove valve covers one has to briefly remove the
Camshafts due to the presence of a spacer and the lash adjuster socket on the rocker. Label each of the rocker arms to know how to relocate them back into position and then remove it from the engine. With the rocker arms pulled out, the hydraulic lash adjusters can be accessed and extracted out of the cylinder head, their original position should be maintained for reused items. Check each rocker arm for signs of wear, cracks, and other kinds of damage at the areas that it makes contact with the valve stem; the rollers should be slippery to slide over, but if they are binding or rough, or if they make the bearings wobble, this is a clear sign that the rocker arm needs to be replaced as the bearings it is using are spoiled. That is right, these engines do not have provision for valve adjustments and therefore any wear or damage in the valve train will cause the valve clearance to increase and there will be noise when the machine is in operation. Check that the oil passage hole existing in each hydraulic lash adjuster is free. Camshaft lifter prelube should be applied to the pivot pockets, the roller and the slot that makes contact with the valve within the rocker arm to which it will be installedThe hydraulic lash adjusters get clean engine oil put into the bores before being installed into the cylinder head and the rocker arm fitted over the lash adjusters. The last procedures in it are the reverse of the above mentioned removal process, and before starting the engine, replace the oil and insert a new oil filter.