Camshaft: Service and Repair
Camshafts
Special tools, testers and auxiliary items required
• Thrust Piece (T10174)
• Assembly Tool (T10352)
• Counter Hold Tool (T10355)
• Locking Pin (T40011)
• Ignition Coil Puller (T40039)
• Torque Wrench (5-50 Nm) (V.A.G 1331)
• Silicone Sealant (D 154 103 A1)
• The sealing surfaces of the cylinder head cover and the cylinder head must not be reworked.
• The camshaft bearings are integrated in the cylinder head and the cylinder head cover. The tension must be released from the camshaft timing chain before removing the cylinder head cover.
• If the cylinder head cover was loosened, the seal must be replaced.
• During installation, cable ties must be installed at the same location.
Removing
- Remove the engine cover. Refer to => [ Engine Cover ] Engine Cover.
- Remove the vacuum pump. Refer to => [ Vacuum Pump ] Vacuum Pump.
- Remove the noise insulation.
- Remove the front part of the right wheel housing liner and/or the front right wheel housing liner.
- Remove the bolts - arrows -.
- Remove the charge air pipe by lifting the clamps - items 1 and 2 -.
- Disconnect the connector from the camshaft adjustment valve 1 (N205) - 1 -.
- Remove the bolts - arrows - and then the camshaft adjustment valve 1.
- Remove the upper timing chain cover. Refer to => [ Upper Timing Chain Cover ] Upper Timing Chain Cover.
The control valve has left hand threads.
- Remove the control valve in the - direction of the arrow - using assembly tool (T10352).
- Remove the bolts - arrows - and remove the bearing bracket.
- Rotate the vibration damper using counter hold tool (T10355) into the Top Dead Center (TDC) position.
• The notch on the vibration damper must line up with the arrow mark - arrow - on the lower timing chain cover.
- Mark the chain/sprockets - arrows - with a waterproof marker. These marks are necessary for reinstallation.
- Remove the plug - arrow -.
- Lift the chain tensioner locking wedge by inserting a scribe or a suitable screwdriver into the hole in the chain tensioner - direction of arrow 1 -.
- Turn the crankshaft opposite the engine rotation direction - arrow direction 2 - and secure it using locking pin (T40011).
• The intake camshaft switches in the engine rotation direction.
- Remove the bolt - 1 - and guide the tensioning rail - 2 - downward.
- Remove the upper guide rail - 3 - by unlocking the latch located in the center with a screwdriver and pushing the guide rail forward.
• When the lower timing chain cover is installed, the loose chain on the crankshaft can not jump off.
- Remove the camshaft timing chain from the sprockets.
Danger of damaging the valves, piston head and lower timing chain cover.
• If the camshaft timing chain was removed from the cylinder head, then the crankshaft may not be turned further.
• On this engine, when the valves are mounted, there is the danger that there are panels attached to the lower timing chain cover, which could fall and interfere with the chain; also a loose chain turned by the crankshaft can bend the panels. The panels can bend if the crankshaft is rotated when the chain is loose.
- Disconnect the connectors from the ignition coils and free up the wiring harness.
- Remove the ignition coils using ignition coil puller (T40039).
- Disconnect the hose - 1 - for the crankcase ventilation.
- Remove the bolts - arrows -.
- Remove the charge air pipe bolt - arrow -.
- Loosen the hose clamp - 2 - and remove the charge air pipe together with the crankcase ventilation.
- Disconnect the vacuum line - 1 - and free up the wire.
- Disconnect the electrical connector - 2 - from the Camshaft Position (CMP) sensor (G40).
- Remove the cylinder head cover bolts in sequence - 1 through 6 -.
- Remove the cylinder head cover.
- Remove the camshafts.
- Prevent dirt and adhesive residue from entering the cylinder head.
Installing
• Tightening specifications, refer to => [ Valvetrain Overview ] Service and Repair.
• Sealing surfaces must be completely free of oil and grease.
• The pistons must not be positioned at TDC.
• Make sure that all roller rocker levers make contact correctly on the valve stem ends.
• Note the expiration date of the silicone sealant.
• The cover must be installed within 5 minutes after application of silicone sealant.
- Remove any sealant residue from the cylinder head using a flat blade scraper.
Wear safety glasses.
• Prevent dirt and adhesive residue from entering the cylinder head.
- Remove any sealant out of the groove in the cylinder head cover as well as from any sealing surface using, for example, a rotating plastic brush.
- Clean sealing surfaces, must be free of oil and grease.
- Cut the tube nozzle at the front mark (nozzle diameter approximately 2 mm).
- Lubricate the running surfaces of both camshafts.
- Place the camshaft into the cylinder head; the recesses - arrows - must be perpendicular to each other.
- Replace the cylinder head cover bolts.
- Apply silicone sealant (D 154 103 A1) on the clean sealing surface of the cylinder head cover as shown - arrows -.
• Sealant bead thickness: 2 to 3 mm.
• The cylinder head cover must be installed within 5 minutes after application of silicone sealant.
• The sealant bead may not be thicker than specified, otherwise the excess sealant could enter the oil pan and clog the oil intake tube.
• Note the expiration date of the sealing compound.
- Tighten the bolts in several stages and in sequence, refer to => [ Cylinder Head Cover Bolt Tightening
Sequence and Specification ] Service and Repair.
• Make sure the cylinder head cover is not tilted.
• Install the cap - 1 - without sealant using thrust piece (T10174).
• Dimension - a - 1 - 2 mm
When rotating the crankshaft, make sure the timing chain cannot damage any other components.
- Rotate the vibration damper using (T10355) into the TDC position.
• The notch on the vibration damper must line up with the arrow mark - arrow - on the lower timing chain cover.
• The marked links of the timing chain must be positioned on the marks on the sprockets.
- Mount the camshaft timing chain: the chain/sprocket marks - arrows - must align.
- Turn the intake camshaft using a wrench in the - direction of the arrow - and mount the timing chain.
The rest of the installation is basically a reverse of the removal sequence.