All of the engines covered by this guide are equipped with hydraulic valve adjusters. Because of this, there is no valve adjustment. Excess clearance between the tip of the valve and the rocker is taken up by engine oil pressure acting against a plunger in the adjuster.
If abnormal noise is heard from the lash adjusters check as follows:
- Start the engine and allow to idle until normal operating temperature is reached. Shut the engine OFF .
- While installed to the cylinder head, press the part of the rocker arm that contacts the lash adjuster. The part pressed will feel very hard if the lash adjuster condition is normal.
- If, when pressed, it easily descends all the way downward, replace the lash adjuster.
- If there is a spongy feeling when pressed, air is probably mixed in, and so the cause should be investigated. The cause is probably an insufficient amount of engine oil, or damage to the oil screen and/or gasket.
- After finding the cause and taking the appropriate step, warm up the engine and drive at low speed for a short time. Then after stopping the engine and waiting a few minutes, drive again at low speed. Repeat this procedure a few times to bleed the air from the oil.