Cylinder Head Cover
Cylinder Head Cover
• Only remove the plastic protectors installed to protect the open valves immediately before positioning the cylinder head.
• When replacing the cylinder head or cylinder head gasket, the coolant must be completely replaced.
• Cylinder heads with cracks between the valve seats can continue to be used without reducing service life, as long as the tears have a width of max. 0.5 mm.
• After working on the valvetrain and lifters, carefully rotate the crankshaft by hand at least 2 full revolutions before starting to be sure that valves do not strike the pistons.
• Always replace self-locking nuts, seals, gaskets and clamps.
Special tools, testers and auxiliary items required
• Torque Wrench (V.A.G 1331)
• Spring-type clip pliers (VAS 6362)
• Socket (T40055)
• Ratchet (V.A.G 1331/1)
• Engine bung set (VAS 6122)
CAUTION!
• Follow the safety precautions when working on the diesel direct injection system. Refer to --> [ Safety Precautions ] Safety Precautions.
• Observe rules for cleanliness. Refer to --> [ Clean Working Conditions ] Clean Working Conditions.
Always follow these instructions before and during work.
• Refer to --> [ Cylinder Head Cover Assembly Overview ] Cylinder Head Cover Assembly Overview.
Removing
CAUTION!
When doing any repair work, especially in the engine compartment, pay attention to the following due to clearance issues:
• Route lines of all types (e.g. for fuel, hydraulic, EVAP canister system, coolant and refrigerant, brake fluid, vacuum) and electrical wiring so that the original path is followed.
• Ensure sufficient clearance to all moving or hot components.
- Remove engine cover. Refer to--> [ Engine Cover ] Engine Cover.
- Remove protective strip. Refer to --> [ 3 Protective Strip ] Cylinder Head Cover Assembly Overview.
- Remove connector on fuel injectors - A -, the exhaust pressure sensor 1 - B - and fuel pressure sensor - C -.
- Remove coolant line bolts - arrows - from intake manifold and lay the line in front of the intake manifold.
- Unclip wiring harness from wiring guide for the glow plugs.
CAUTION!
Always follow the correct procedure for disconnecting glow plug connectors!
- Remove glow plug connectors. Refer to --> [ Glow Plug Connectors ] Glow Plug Connectors.
- Remove fuel return line bolt. Refer to --> [ item 3, 8 Nm ] Removal and Replacement on the intake manifold.
- Loosen hose clip - arrow - with the hose clip pliers (VAS 6362) and remove the line on the rail element (high pressure reservoir).
- Before removing, clean return line connection on the fuel injectors (for example using a commercially available detergent).
- Dry return line connections.
- Cover return line connections with a rag.
- Remove fuel return line connections on the fuel injectors. Pull them upward to release them - arrow -.
• Maintain clean working conditions. Dirt and contaminants must not enter the return lines and the connections on the fuel injectors.
- Loosen hose clip with hose clip pliers (VAS 6362) and remove fuel return line --> [ 4 Fuel Return Line ] Removal and Replacement.
- Loosen hose clip - 4 - with the hose clip pliers (VAS 6362) and remove the fuel return line at the high pressure fuel pump.
- Seal lines so that the fuel system is not contaminated by dirt etc.
- Remove fuel return lines --> [ 2 Fuel Return Lines ] Removal and Replacement and lay them in front of the intake manifold.
- Remove connector from charge pressure actuator position sensor - arrow - at the turbocharger vacuum diaphragm and guide the line out of the retainers.
- Remove connector from the fuel pressure regulator valve - arrow -.
- Remove line guide on the rail element (high pressure reservoir) and lay it aside.
- Remove vacuum hose --> [ 11 Vacuum Hose ] Cylinder Head Cover Assembly Overview at the cylinder head cover.
- Remove remaining vacuum hoses from the bracket on the cylinder head cover.
- Remove connector - 1 - from the engine coolant temperature sensor on radiator, open the clips - arrows - and remove upper section of the toothed belt guard.
- Remove crankcase ventilation hose between the intake scoop and the cylinder head cover.
• The crankcase ventilation hose is destroyed when it is removed.
- Remove high pressure line --> [ 21 High Pressure Lines, 25 Nm ] Removal and Replacement between the high pressure fuel pump and rail element (high pressure reservoir).
- Remove high pressure lines --> [ 5 High Pressure Lines ] Removal and Replacement between the rail element (high pressure reservoir) and fuel injectors.
- Remove bolts - arrows - and the rail element (high pressure reservoir).
- Remove fuel injectors. Refer to--> [ Fuel Injection Unit ] Service and Repair.
- Remove cylinder head cover bolts in sequence - 7 to 1 -.
- Remove cylinder head cover.
Installing
Install in reverse order of removal, noting the following:
• Replace cylinder head cover if damaged or leaking.
• When installing the high pressure line or fuel lines, make sure no dirt or contaminants enter the fuel system.
• Only remove the sealing plugs right before installing the fuel lines.
• Do not change the angles of the high pressure lines
• Make sure lines connections are securely fastened.
• Do not swap supply and return lines.
- First tighten cylinder head cover bolts by hand in sequence - 1 to 7 -.
- Then tighten cylinder head cover bolts to the specification in sequence - 1 to 7 -.
• Tightening specifications, refer to --> [ 14 10 Nm ] Cylinder Head Cover Assembly Overview.
- Install upper section of the toothed belt guard.
- Make sure upper toothed belt guard section is clipped to the cylinder head cover correctly.
• The illustration shows the camshaft sprocket removed.
- Press upper section of the toothed belt guard in the area with the clips - arrows - against the cylinder head cover until the clips engage with each other. Use a screwdriver to press the guard if necessary.
- Check clearance between the hub and upper section of the toothed belt guard.
- Tighten high pressure line union nuts by hand.
- Make sure high pressure line is free of tension.
- Use torque wrench (V.A.G 1331) with the ratchet (V.A.G 1331/1) and socket (T40055) to tighten high pressure line.
Tightening specifications:
• Refer to --> [ Cylinder Head Cover ] Cylinder Head Cover.
• Refer to --> [ Fuel System Assembly Overview ] Removal and Replacement.
- Fill the fuel system. Refer to --> [ Fuel System, Filling ] Fuel System, Filling.