Jeep 4777976AA Valve Lifter

The valve lash adjuster is an integral part of each rocker arm and cannot be replaced separately. Begin by removing the rocker arm shafts without detaching the rocker arms from the shafts. Next, turn the rocker arm assembly upside down on the workbench and inspect each lash adjuster for signs of wear and damage, especially on the surface that contacts the valve tip. Since lash adjusters often become clogged, it is advisable to replace the rocker arm/lash adjuster assembly if there are concerns about their condition or if the engine is making valve "tapping" noises. If any lash adjusters were removed, reassemble the rocker arms onto their shafts. Ensure that the lash adjusters are partially filled with engine oil, which is indicated by minimal plunger action when depressed. If there is excessive plunger travel, immerse the rocker arm assembly in clean engine oil and pump the plunger until the travel is eliminated. If the plunger still moves within the rocker arm when filled with oil, it is defective, and the rocker arm assembly must be replaced. Upon restarting the engine after replacing the rocker arm/lash adjusters, expect the adjusters to make "tapping" noises. After warming up, increase the engine speed from idle to 3,000 rpm for one minute; if the adjusters do not become silent, replace the defective rocker arm/lash adjuster assembly.