Hydraulic valve lifters, checking
WARNING: This page is about a different variant/trim than selected.
Special tools, testers and auxiliary items required
- Feeler gauge
- Wooden or plastic wedge
NOTE:
- Replace complete valve lifters only (cannot be adjusted or serviced).
- Irregular valve noises are normal while starting the engine.
Test sequence
- Start engine and let it run until engine oil temperature has reached min. 80 ° C.
- Increase engine speed to approx. 2500 RPM for 2 minutes.
If hydraulic valve lifters are still noisy, determine which lifter is defective as follows:
- Remove cylinder head cover.
- Turn crankshaft clockwise until camshaft lobe for valve lifter to be tested is pointing upward.
- Check clearance between cam lobes and valve lifters.
- If play is greater than 0.1 mm, replace valve lifter. If minimal play of 0.1 mm or no play is measured, continue procedure as follows:
- Press valve lifter downward with a wood or plastic wedge. If there is a gap of more than 0.1 mm until the valve begins to open, replace lifter.
NOTE:
- After installing new valve lifters, the engine may not be started for approx. 30 minutes. The hydraulic equalization elements must seat themselves (otherwise the valves will crash into the pistons).