Bleeding the Lash Adjuster System

NOTES
^ Parking the vehicle on a grade for a long time may leak oil from the lash adjuster, causing air to enter the high pressure chamber when starting the engine.

^ After being parked for many hours, oil may run out from the oil passage. It takes time before oil is supplied to the lash adjuster, causing air to enter the high pressure chamber.

^ In the above cases, eliminate the abnormal noise by bleeding the lash adjusters as follows:





1. Check the engine oil. Add or change oil if required.

NOTES
^ If the engine oil level is low, air is sucked from the oil screen, causing air to enter the oil passage.

^ If the engine oil level is higher than specification, oil may be stirred by the crankshaft, causing oil to be mixed with air.

^ If oil is deteriorated, air is not easily separated from oil, increasing the quantity of air contained in oil.

^ If oil mixed with air enters the high pressure chamber inside the lash adjuster from the above causes, air in the high pressure chamber is excessively compressed while the valve is opened, resulting in abnormal noise at closing of the valve. This is the same phenomenon as when the valve clearance has become excessive. The lash adjuster can resume normal function when air that has entered the lash adjuster is removed.

2. Idle the engine for 1 to 3 minutes.





3. Repeat the operation pattern shown, at no load to check for abnormal noise. (Typically the abnormal noise is eliminated after repeating the operation 10 to 30 times. If no change is observed in the abnormal noise after repeating the operation 30 times, it is suspected that the abnormal noise is due to some other factors.)





4. After elimination of abnormal noise, repeat the operation shown, five more times.

5. Run the engine at idle for 1 to 3 minutes to make sure that the abnormal noise has been eliminated.

6. If abnormal noise is not eliminated, replace the lash adjuster.