To isolate a noisy valve lash adjuster, place a length of hose or tubing near each valve while listening at the other end, or remove the rocker arm cover and touch each valve spring retainer with the engine idling; a defective lash adjuster will be noticeable through the shock felt at the retainer as the valve seats. The most common cause of noise is dirt trapped between the plunger and lash adjuster body. Begin by removing the rocker arm cover, then loosen both rocker arm bolts at the cylinder with the noisy lash adjuster and rotate the rocker arms away from the pushrods before removing the pushrod guide plates and pushrods. Next, take off the intake manifold and the pushrod cover. Unscrew the pushrod cover studs to remove the lash adjuster guide retainer and then the lash adjuster guide, keeping them in order if multiple guides are removed. Lash adjuster extraction can be done using a special hydraulic tool, but often a small magnet or fingers suffice on newer engines without varnish buildup; a small scribe may also help, but avoid using pliers unless replacing the lash adjuster to prevent damage. Store the lash adjusters in a clearly labelled box to ensure they are reinstalled in their original bores. Replacing a worn lash adjuster is generally easier than repairing a defective one, as internal components are not sold separately. If cleaning a dirty lash adjuster, disassembly may restore normal function. When installing, ensure lash adjusters are placed back in their original bores, coating each foot with moly-base grease or engine assembly lube, and lubricate the bearing surfaces of the lash adjuster bores with engine oil. Install the lash adjusters with the oil orifice facing the front of the engine, followed by the lash adjuster guides and retainers. Reinstall the pushrods, guide plates, rocker arms, and retaining bolts, ensuring each pair of lash adjusters is on the base circle of the camshaft before tightening the bolts to the specified torque. Finally, reinstall the pushrod cover, intake manifold, rocker arm cover, and air cleaner.
