Hydraulic Lash Adjuster

6. Hydraulic Lash Adjuster
The hydraulic lash adjuster is built into each rocker arm on the valve side. A total of sixteen lash adjusters are employed.
- When valve opens:
When the camshaft rotates, the HLA body is pushed to the right direction via the rocker arm. However, as the HLA plunger is pushed back to the left direction by the reaction force of valve stem, the hydraulic pressure is generated in chamber A and check ball plugs the oil passage. When the hydraulic pressure in chamber A increases according to the cam lobe lift and overcoming the valve spring tension, valve stem moves to the right and valve opens.
- When valve closes:
When the camshaft rotates further and the valve closed, the hydraulic pressure in chamber A drops.
Then the hydraulic pressure in rocker arm oil reservoir overcomes the hydraulic pressure in chamber A, the check ball opens and engine oil flows into chamber A.
- While valve is closed condition, the HLA plunger is pushed toward the valve stem by plunger spring force, and valve clearance always maintaining to 0 mm (0 in).