Auto Lash Adjuster Construction These engines have auto lash adjusters that eliminate the need for valve clearance adjustment and reduce noises of the valve system. The auto lash adjuster automatically absorbs change in the valve clearance caused by engine temperature change or wear of parts and adjusts the valve clearance always to zero. Operation of Auto Lash Adjuster (1) At Start of Valve Lift When the cam lifts up the rocker arm, the hydraulic pressure immediately forces the ball in the high pressure chamber against the seat, closing the high pressure chamber.
(2) During Valve Lift A small amount of oil leaks from the high pressure chamber through a clearance between the body inside and the plunger outside. (3) At end of Valve Lift The plunger spring forces the body back to the initial position and oil is supplied to the high pressure chamber to make up for the leaked oil. G424 Service Manual Engine System 27