A noisy lash adjuster can be isolated while the engine is idling by using a mechanic's stethoscope or a length of hose near each valve, listening at the other end, or by removing the valve cover and touching each valve spring retainer one at a time to feel for shock if a adjuster is defective. Common causes of noisy adjusters include dirt trapped inside and insufficient oil, so it's important to check the oil for fuel contamination, level, cleanliness, and viscosity before making any judgments. To remove the adjusters, first take off the valve cover and lower intake manifold, then remove the
Rocker Arms and
Pushrods. Next, take out the bolts holding the roller adjuster guides to the block and remove the guides, marking them for reinstallation. Adjusters can be extracted using a special tool, a small magnet, or a machinist's scribe, but caution is advised against using pliers unless replacing the adjusters, as they may cause damage. Store the adjusters in a labeled box to ensure they are reinstalled in their original locations. Since parts for lash adjusters are not sold separately, cleaning them is often more practical than replacement. Thoroughly clean and dry the adjusters, checking for scuffing, score marks, or uneven wear, and inspect the rollers for wear or damage. When reinstalling used adjusters, ensure they go back into their original bores, soak new adjusters in oil, and coat all adjusters with moly-base grease or engine assembly lube before installation. Finally, install the adjusters and guides, tighten the bolts to the specified torque, and run the engine to check for oil leaks.