Valve clearance — adjustment

Special tool

	Valve Tappet Compressor 303-563 (21218)
	Valve adjusting shim removal/installation tool 303-563-01 (2121801)
	Spark Plug Pliers 303-622 (21226)

General equipment:

• Set of feeler gauges
• Micrometer

Name	Specification
Silicone grease	A960-M1C171-AA

Adjustment

1. Disconnect the ground cable from the battery. For additional information, refer to Section 414-01.

2. Remove the cylinder head cover.

• 1. Release the fuel lines.
• 2. Disconnect the crankcase ventilation hose.
• 3. Release the carbon filter vacuum line bracket.
• 4. Unscrew the bolts (six bolts).

3.

CAUTION: When disconnecting the spark plug connector, do not pull on the wire. If necessary, remove the ignition coil to avoid bending the wire. Before removing, slightly rotate the spark plug connector to release the gasket.

CAUTION: Disconnect the spark plug connector using straight-line force only.

CAUTION: Do not damage the cylinder head cover gasket as it cannot be replaced individually.

Remove the cylinder head cover by moving it straight up.

• 1. Disconnect the plug connector of the cylinder head temperature sensor (CHT).
• 2. Disconnect the high tension wires from the spark plugs.
• For angled spark plug connectors, use special tool 303-622.
• 3. Remove the three bolts from the upper timing belt cover.
• 4. Unscrew and remove the nuts.

4.

NOTE: Install long bolts at the front.

Connect the special tool.

• Remove the outer bolts from the first and last camshaft bearing caps.
• Install the special tool so that the compression tool guide faces outward.

5.

NOTE: The cam of the valve in question must be facing up.

Attach the special tool. Insert the compression tool into the lever.



6. Determine the valve clearance in the valves of the first cylinder.





8.

NOTE: The tappet groove must face the center of the engine.

NOTE: Do not press on the adjusting shim with the compression tool.

Remove the adjusting shim.

• 1. Attach the compression tool to the end of the valve lifter and press down on the lifter.
• 2.Remove the adjusting shim.

9. Use a micrometer to determine the thickness of the adjusting shim.

10. Select a new adjusting shim. Determine the thickness of the new adjusting shim: The thickness of the adjusting shim (new) is determined as the value of the measured valve clearance plus the thickness of the "old" adjusting shim. The thickness of the selected new adjusting shim should differ from the calculated value by no more than 0.03 mm.

11. Insert a new valve adjusting shim of the thickness calculated in accordance with the previous step.

12. Check the valve clearance; if necessary, adjust the valve clearance in accordance with the above points.



13. Perform these steps on each cylinder on the inlet and outlet side respectively.

14. Remove the special tool.



15.

CAUTION: To avoid damaging the spark plug connector seal, use a blunt object (such as a plastic zip tie) to apply silicone grease.

CAUTION: Connect the spark plug connector by applying a straight force to it.

NOTE: Coat the inside of the spark plug connector with silicone grease to a depth of (5-10) mm.

Install the cylinder head cover.

• 1. Install the nuts and tighten them in two stages. Stage 1: 3 Nm. Stage 2: 10 Nm
• 2. Connect the plug connector of the SNT sensor.
• 3. Connect the spark plug connector.
• 4.Install the three timing belt upper cover bolts.

16. Install the cover on the cylinder head cover.

• 1. Screw in the bolts (six bolts).
• 2.Connect the PCV hose.
• 3. Fix the holder of the vacuum line of the carbon filter.
• 4. Secure the fuel lines.

17. Standard finishing operations:

• Connect the ground cable to the battery. Refer to Section 414-01 for additional information.
• If necessary, secure the wires using cable ties.
• Check the fluid levels and adjust them if necessary.