- Start engine and let run until coolant temperature reaches at least 80° C.
- Increase RPM to 2500 for approx. 2 minutes, if necessary road test vehicle. NOTE: If unusual valve noises disappear but then reappear during drive, replace oil retaining valve. Oil retaining valve, component location: Below cover at intake manifold. See «OIL CHECK VALVES AND SPRAY JET VALVE, OVERVIEW»(ref-197058-S08392965762005101100000) .
If hydraulic valve lifters are still loud, locate faulty valve lifter as follows
Scheme 306
Scheme 307
- Remove cylinder head cover. See «LEFT CYLINDER HEAD COVER, REMOVING AND INSTALLING»(ref-197058-S15360340212005101100000) or «RIGHT CYLINDER HEAD COVER, REMOVING AND INSTALLING»(ref-197058-S38907741232005101100000) .
- For vehicles with auxiliary heater, remove bolts (arrows) for exhaust pipe of parking heater/auxiliary heater on noise insulation.
- Remove bolts or quick-release screws -1 - and -2- and remove front noise insulation.
- Turn crankshaft at center bolt of toothed belt gear clockwise until the cams of the cylinder to be checked point upward (arrows).
- Determine play between cams and valve lifters.
- Press valve lifter downward using wooden or plastic wedge. If 0.20 mm feeler gauge can be inserted between camshaft and valve lifter, replace valve lifter.
- Valve lifters, replacing, see «CAMSHAFTS AND CAMSHAFT ADJUSTERS, REMOVING AND INSTALLING»(ref-197058-S08890454852005101100000) NOTE: After installing camshaft, do not start engine for at least 30 minutes. The hydraulic valve lifters have to settle (otherwise valves will strike the pistons). After working on the valvetrain, carefully rotate engine by hand at least 2 full revolutions to ensure that valves do not strike the pistons when starting.
Scheme 308
- Adapter T40012
- 3122B spark plug removal tool
- 3364 Valve Seat Tool
- 3365 Valve Stem Seat Fitting Tool
- VAS 5161 removal and installation device