All of the engines covered by this manual 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.