To identify which of the valves of an engine is accompanied with a noisy valve lash adjuster, place a hose or tubing at each intake and exhaust valve during a running of the engine then listen to the noise at one end of the hose or tubing. Otherwise, if you take off the rocker arm cover and with the engine running, touch each of the valve spring retainers; you will feel the faulty lash adjuster through the retainer as the valve seats. As Schaevitz's warning suggests however, if adjustments are correct, dirt trapped between the plunger and lash adjuster body is often the root cause. Start with the L4 rocker arm cover followed by the intake manifold; L4 engines should have the pushrod cover also removed. Turn the nut of the rocker arm counterclockwise to get the rocker arm out of the pushrod area and then remove the pushrod. In removing the lash adjusters, one can use a special lash adjuster removal tool, or even just a sharp scribe so as not to mar the lash adjuster body in any way. Retain the lash adjusters for the purpose of reassembly in their respective sites. To dismantle a valve lash adjuster, apply pressure to the top of the plunger by inserting a pushrod to remove the pushrod seat retainer, pushrod seat, and metering valve by using a small screwdriver. The following components should be taken out, namely the plunger, ball check valve, plunger spring; the ball check valve will require use of a small screwdriver to remove in addition to the spring. Check all parts for signs of wear and where possible have the complete lash adjuster assembly replaced if any defects are noticed on the ball, particularly if there are flat spots on it. Each lash adjuster should have its camshaft lobe mating surface checked for scoring, wear, or erosion, any such texture on the lash adjuster body requiring its replacement while wear in the lash adjuster bore is rare. For reassembly, place the check ball on the small hole in the bottom of the plunger, insert the check ball spring on the seat in the ball retainer and fix the retainer. After that, insert the plunger spring over the ball retainer, turn the lash adjuster body upside down and make certain the oil holes are in proper orientation to each other before flooding the compartment with SAE 10 oil. Last but not least, fit the metering valve and the pushrod seat; push the seat in place and fix it by fitting the pushrod seat retainer. They must be replaced on their original bores and their surfaces should be treated with Molykote or an equivalent lubricating alloy before reinstalling them by reversing the above process.
