2. If the noise level emitted by the valve mechanism increases, the hydraulic tappets should be checked for proper operation.
3. Warm up the engine to normal operating temperature. Raise the engine speed to 2500 rpm for a couple of minutes (fast idle speed), then turn off the engine. Remove the cylinder head cover (see section Removal and installation the cylinder head cover).
4. Turning the engine by the crankshaft bolt, position the cam of the first cylinder of the camshaft with the working projection upward.
5. Using a feeler gauge, measure the clearance between the cam heel and the end face of the hydraulic tappet assembly. If the measurement result exceeds 0.1 mm, the tappet should be replaced.
6. At normal gap size (less than 0.1 mm) rest against the upper end of the pusher and press it down until it stops against the valve stem.
Note: The pusher should only be pressed using a tool made of soft material (wood, plastic).
7. If the stroke of the pusher before it hits the valve stem exceeds 0.1 mm, the assembly is faulty and must be replaced.
Caution: After installing hydraulic tappets, wait at least 30 minutes before starting the engine (it is recommended to postpone the launch until the next morning), otherwise, the risk of pistons colliding with valves cannot be completely eliminated!