Camshaft, Lifters and Push Rods: Service and Repair

Valvetrain Assembly Overview





1 Bolt, 8 Nm + 90° (1/4 turn) additional turn

• Always replace.

2 Guide frame

• Removing and installing, refer to --> [ Camshafts ] Service and Repair.

• With integrated camshaft bearings.

• Clean the sealing surface, reworking is not permitted.

• Remove the old sealant residue.

3 Chain sprocket

• For the exhaust camshaft.

4 Bolt, 60 Nm + 90° (1/4 turn) additional turn

• Always replace.

5 Bolt, 60 Nm + 90° (1/4 turn) additional turn

• Always replace.

6 Camshaft adjuster

• For the intake camshaft.

7 Seals

• For the camshaft adjuster.

• Note the installed position, refer to --> [ Camshafts ] Service and Repair.

8 Timing chain

• Removing from adjuster and sprocket, refer to --> [ Valve Timing, Adjusting ] Adjustments.

9 Cylinder head

• Do not regrind the valve seats, only lapping is permitted.

10 Hydraulic valve play balancing element

• Do not interchange.

• Lubricate the contact surface.

11 Valve retainers

12 Top valve spring retainer

13 Valve spring

14 Valve stem seal

• Replacing, refer to --> [ Valve Stem Seals ] Service and Repair.

15 Valve guide

• Checking, refer to --> [ Valve Guides, Checking ] Testing and Inspection

16 Intake valve

• Do not rework, only lapping is permitted.

• Valve dimensions, refer to --> [ Valve Dimensions ] [1][2]Specifications.

• Check valve guides, refer to --> [ Valve Guides, Checking ] Testing and Inspection.

17 Exhaust valve

• Do not rework, only lapping is permitted.

• Valve dimensions, refer to --> [ Valve Dimensions ] [1][2]Specifications.

• Check valve guides, refer to --> [ Valve Guides, Checking ] Testing and Inspection.

18 Sealing plugs

• Replace

• Installing, refer to --> [ Camshafts ] Service and Repair.

19 Intake camshaft

• Removing and installing, refer to --> [ Camshafts ] Service and Repair.

• Check radial clearance using Plastigage (roller rocker lever removed).

Wear limit: 0.1 mm.

• Run out: max. 0.035 mm.

• Axial clearance: max. 0.17 mm.

20 Exhaust camshaft

• Removing and installing, refer to --> [ Camshafts ] Service and Repair.

• Check radial clearance using Plastigage (roller rocker lever removed).

Wear limit: 0.1 mm.

• Run out: max. 0.035 mm.

• Axial clearance: max. 0.17 mm.