Valve Clearance: Service and Repair
Special Tools
999 5006
999 5383
999 5460
999 5452
999 5199
999 5452
999 5454
999 5670
999 5765
999 5752
999 5451
951 2767
999 5454
999 5719
999 5718
Note! As the illustrations in this service information are used for different model years and/or models, some variation may occur. However, the essential information in the illustrations is always correct.
Preparation
Remove:
- the cable from the battery negative terminal. First read Note when disconnecting and connecting the battery lead.
Removing the starter motor
Remove:
- the screws for the starter motor
- the support bracket for the intake manifold
- the connector for the oil pressure switch
- unhook the starter motor and allow it to hang.
Removing components
Remove:
- the cover over the injector
- the cover over the Throttle Body (TB)
- the upper timing cover
- the cover over the ignition coils
- front timing cover
- the inlet hose between the Mass Air Flow Engine (MAP) sensor and Throttle Body (TB)
- the auxiliaries belt.
Exposing the cable harness
Remove:
- the screw from the ignition coil ground
- the camshaft position (CMP) sensor.
Remove:
- the variable valve timing valve connector
- the ignition coil connectors.
Place the cable harness to one side.
Unscrew the cable duct from the rear edge of the cylinder head and the Throttle Body (TB) bracket.
Remove:
- the connector for the engine coolant temperature sensor
- the injector connectors.
Place the cable duct and cable harness to one side.
Mark up and remove the ignition coils and ignition cables.
Remove:
- the rear cover for the camshaft
- the Camshaft Position (CMP) sensor housing
- the trigger wheel
- the hose for the crankcase ventilation from the camshaft cover.
Installing the lifting beam and lifting hook
Install the lifting beam and the lifting hook according to Replacing the timing belt, refer to Timing Components, Timing Belt.
Removing the right-hand engine mounting
Remove the right engine mounting according to Replace the engine mountings, refer to Drive Belts, Mounts, Brackets and Accessories, Engine Mount.
Position the engine according to the marking
See Replacing the timing belt, Refer to Timing Components, Timing Belt.
Removing the timing belt
Remove the timing belt according to Replacing the timing belt, Refer to Timing Components, Timing Belt.
Removing the timing gear pulley
Remove the timing gear pulley according to Removing the camshaft seals/variable valve timing unit, refer to Camshaft, Lifters and Pushrods, Camshaft Oil Seal.
Removing the camshaft cover
Note: Do not remove the cylinder head.
Remove the camshaft cover, see Replacing the cylinder head and gasket. Service and Repair
Cleaning
Use a razor blade or a gasket scraper and gasket solvent P/N 1161 440 on the camshaft cover.
Warning Use a fume hood or extractor when using gasket solvent. Use only a gasket scraper or razor blade on the cylinder head.
Note! Take great care around the oil ducts for the variable valve timing solenoid. This applies to both the camshaft cover and the cylinder head. The solenoid is extremely sensitive to contaminants.
Dry and blow all surfaces clean.
Preparations
Carefully tap the end of the valve stem to ensure that the valve is correctly located in the seat. Use a plastic aluminum or brass drift to protect the valve and the surface of the valve lifter.
The sound made by tapping reveals if the valve is correctly seated.
Installing the valve lifters and camshaft
Install both the valve lifters for the inlet valves at cylinder 1.
Check the notes made earlier. Select new valve lifters if necessary.
Note! Only install two valve lifters. The valve lifters must be placed at the same cylinder.
The valve clearance on a cold engine (approximately 20°C/68°F) must be:
Reference Values
Note! The tolerances are less at setting! When checking the valve clearance through the plug hole the tolerances are larger.
Install the intake camshaft. Ensure that the lobes at cylinder 1 point upwards.
Apply a little oil to the cam lobe and the upper side of the valve lifter to facilitate measurement later.
Installing the camshaft press
Install the lower section of camshaft press 999_765 at the intake valves for cylinder 1.
Tighten the tool against the cylinder head.
Tighten to 17 Nm.
Turn the camshaft until it stops against the camshaft press.
Install the upper section of the camshaft press.
Tighten the screw which tensions the camshaft.
Tighten to 12 Nm.
Measuring the valve clearance
Note! Measurement must be carried out on a cold engine. A suitable temperature is approximately 20°C/68°F.
Use feeler gauge 999 5752.
Press with a finger so that the feeler gauge lies parallel to the upper side of the tappet (see illustration).
Move the feeler gauge sideways when taking the reading in order to obtain as accurate a measurement as possible.
The valve clearance on a cold engine (approximately 20°C/68°F) must be:
Reference values
Note! The tolerances are less at setting! When checking the valve clearance through the plug hole the tolerances are larger.
Differences in valve clearance for different engines/ambient temperatures:
- -0.01 mm at 15°C
- +0.01 mm at 25°C
- +0.02 mm at 30°C
- +0.03 mm at 35°C
- +0.04 mm at 45°C.
Correcting the measured clearance
Lift out the upper section of the press tool.
Lift out the camshaft.
Adjust the play by replacing the valve lifters.
Other valve lifters are available as replacement part/replacement part kits.
Reinstall the camshaft and the upper section of the press tool.
Tighten to 12 Nm.
Take a new measurement according to Checking valve clearance, refer to Testing and Inspection, Procedures.
When the correct valve clearance is reached
Remove:
- press tool 999 5765
- the camshaft
- the valve lifters.
Carefully mark the valve lifters so that exact reinstallation can be carried out, for example:
- Intake side: I1, I2, I3 through I8
- Exhaust side: Al, A2, A3 through A8.
Repeat the procedure for measuring the valve clearance for all cylinders on both the intake and exhaust sides. See Checking valve clearance, refer to Testing and Inspection, Procedures.
Note! For tightening torques not in the text, refer to Specifications, Mechanical.
Installing the valve lifters and camshafts
Lubricate the valve guide wells.
Install all the valve lifters.
Note! Make sure that the lifters are in the same position as before.
Lubricate the camshaft bearing seats.
Install the intake camshaft. Ensure that the groove at the rear edge of the camshaft is above an imaginary center line.
Position the exhaust camshaft. Ensure that the groove at the rear edge of the camshaft is below an imaginary center line.
Applying liquid gasket
Wipe the oil film off the mating surfaces on the camshaft cover and cylinder head.
Install new O-rings around the spark plug wells on the cylinder head.
Apply liquid gasket 116 1059, or equivalent, to the camshaft cover.
Use roller 9S1 2767.
The surface must be completely covered without any excess.
Note! Ensure that no liquid gasket gets into the coolant or oil ducts. Only a thin layer of liquid gasket is required.
Installing the camshaft cover
To install the camshaft adjustment tool, see Replacing cylinder head and gasket, refer to Service and Repair.
Install camshaft adjustment tool 999 5452 at the rear of the camshafts.
Check that the screws securing the adjustment tool to the camshafts and the screws holding the tool together are well tightened.
Installing the front camshaft seal
To install the front camshaft seal, see Replacing the cylinder head and gasket, refer to Service and Repair.
Aligning the crankshaft
To align the crankshaft see Replacing the cylinder head and gasket.
Installing the camshaft timing gear pulley
Install the camshaft timing gear pulley according to Replacing the camshaft seals/variable valve timing unit, refer to Camshaft, Lifters and Pushrods, Camshaft Oil Seal.
Installing the timing belt
Install the timing belt according to Replacing the camshaft seals/variable valve timing unit, refer to Camshaft, Lifters and Pushrods, Camshaft Oil Seal.
Tightening the timing gear pulley
See Replacing the camshaft seals/variable valve timing unit, refer to Camshaft, Lifters and Pushrods, Camshaft Oil Seal.
Check
- Press the belt to check that the indicator on the tensioner moves easily
- Position the upper timing cover.
- Turn the crankshaft two turns. Check that the markings on the crankshaft and camshaft pulley correspond.
Note! Check that the indicator on the belt tensioner is within the marked area.
- Remove the upper timing cover.
Installing the right engine mounting
Screw the engine mounting onto the engine.
Tighten to 67 Nm.
Install the engine mounting screw and nut in the bodywork bracket. Tighten by hand.
Finishing
Remove the lifting beam and lifting hook.
Tighten the engine mounting nut.
Tighten to 98 Nm.
Install:
- the power steering reservoir
- the metal bracket for the power steering hose on the rotation protection for the auxiliaries belt
- the auxiliaries belt
- the rear camshaft cover
- the trigger wheel.
Tighten to 17 Nm
- the Camshaft Position (CMP) sensor housing.
Tighten to 5 Nm
- the hose for the crankcase ventilation on the camshaft cover.
Installing components
Install:
- the ignition coils and ignition cables according to earlier markings
- the connectors on the variable valve timing valve and ignition coils
- the ground lead for the ignition coils
- the camshaft position (CMP) sensor.
Place the cable duct and cable harness in position.
Install:
- the screws for the cable duct on the rear edge of the cylinder head and Throttle Body (TB) bracket
- the connectors for the injectors
- the connector for the engine coolant temperature sensor
- the inlet hose between the Mass Air Flow Engine (MAP) sensor and Throttle Body (TB)
- front timing cover
- the cover over the ignition coils
- the upper timing cover
- the cover over the Throttle Body (TB)
- the cover over the injectors.
Installing the starter motor
Install the starter motor.
Finishing
Check:
- the engine oil level
- the coolant level.
Warm up the engine until the thermostat opens.
Check the engine for leaks.
Top up the coolant if necessary.