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 radiator fan has switched on once.
- Increase engine speed to approx. 2500 RPM for 2 minutes.
If the hydraulic valve lifters are still noisy, determine which lifter or lifters are faulty as follows:
- Remove cylinder head cover.
- Turn crankshaft clockwise until camshaft lobe for valve lifter to be tested is pointing upward.
- Measure play between camshaft lobe and valve lifter.
- If play is greater than 0.2 mm, replace valve lifter. If minimal play of 0.1 mm or no play is measured, continue procedure as follows:
- Lightly press valve lifter downward with a wood or plastic wedge. If 0.20 mm thick feeler gauge can be inserted between camshaft and valve lifter, replace valve 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).