Mopar 4387678 Engine Valve Tappet

Check the hydraulic lash adjusters for freeplay by inserting a small wire through the air bleed hole in the rocker arm while lightly pushing the check ball down, ensuring the adjuster being tested has the corresponding camshaft lobe pointing away from the rocker arm. While holding the check ball down, move the rocker arm up and down to check for freeplay; there should be a small amount of movement, and if there is no freeplay, replace the adjuster with a new unit. To remove the components, take off the valve cover(s) and the rocker arm shaft components, then pull the hydraulic lash adjuster(s) out of the rocker arm(s), ensuring to label each rocker arm and adjuster and place them in a partitioned box or suitable container to prevent mixing. Installation follows the reverse order of removal.