Valve: Description and Operation

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Hydraulic lash adjusters (HLA) provide automatic valve lash adjustment. The HLAs ride between the camshaft lobes and the top of the valve stems. Any clearance between the lobes and the valve stems is taken up by the hydraulic expansion of each HLA. The HLAs are designed, therefore, to maintain a 0 mm (0 inch) clearance between the camshaft lobes and the valve stems.

The intake valves are located on the inboard side of each cylinder head and the exhaust valves are located on the outboard side of each cylinder head. The exhaust valve stem seals and intake valve stem seals are not interchangeable.