Timing Mechanism Drive Chain and Camshaft Timing Chain
Timing Mechanism Drive Chain and Camshaft Timing Chain
Special tools, testers and auxiliary items required
• Camshaft Bar (T10068 A)
• Counter-Holder Tool (T10069)
• Sealant
Removing
- Removing engine. Refer to => [ Engine, Removing ] Engine, Removing.
- To separate engine and transmission: Vehicles with manual transmission => [ Engine and Manual Transmission, Separating ] Engine and Manual Transmission, Separating, vehicles with direct shift automatic transmission (DSG) => [ Engine and DSG Transmission, Separating ] Engine and DSG Transmission, Separating.
- Remove dual mass flywheel. Refer to => [ Dual Mass Flywheel ] Dual Mass Flywheel.
- Remove intake manifold.
- Remove coolant thermostat housing. Refer to => [ Coolant Thermostat Housing ] Coolant Thermostat Housing.
Vehicles with engine code BUB:
- Remove the hose - 2 - from the secondary air injection (AIR) combination valve.
• Ignore - 1 -.
Vehicles with engine code CBRA:
- Disconnect the hose - 1 - and the vacuum hose - 2 - from the left Secondary Air Injection (AIR) combination valve.
• Ignore - 3 - and - arrows -.
All Vehicles
- Mark and disconnect electrical connectors:
1. Camshaft adjustment valve 1 (exhaust) (N318)
2. Camshaft adjustment valve 1 (N205)
3. Camshaft position sensor (G40)
4. Camshaft position (CMP) sensor 2 (G163)
- Remove Ground (GND) wire - 5 -.
- Disconnect coolant hose - 6 -.
- Remove electrical wiring bracket - arrows -.
- Place bracket with electrical wiring toward front.
- Remove cylinder head cover. Refer to => [ Cylinder Head Cover ] Cylinder Head Cover.
- Remove the oil pan. Refer to => [ Oil Pan ] Oil Pan.
- Adjust crankshaft at vibration damper bolt in direction of engine rotation to "TDC" marking - arrow -.
- Cams - A - of cylinder 1 must face each other.
- At the same time, (T10068 A) must engage in both shaft grooves. Turn crankshaft 1 additional turn if necessary.
- Remove camshaft timing chain tensioner - arrow -.
- Remove the bolts - 1, 2 and 3 -.
The cylinder head seal could be damaged.
• Remove upper timing chain cover horizontally from cylinder head.
- Remove lower timing chain cover bolts - arrow -.
The cylinder head seal could be damaged.
• Remove timing chain lower cover horizontally from cylinder block.
- Press crankshaft sealing ring out of timing chain lower cover.
- Mark timing chain running direction with arrows using paint - arrows - for reinstallation.
Risk of damaging timing chain.
• Do not mark chain with punch, notch or something similar.
- Remove bolts - arrows - and remove guide rail - 1 -.
- Remove camshaft adjuster timing chain from intermediate shaft chain sprocket.
- Carefully remove camshaft timing chain behind cylinder head seal rib.
- Loosen chain sprocket bolt - arrow - approximately 1 turn.
- Counter hold with (T10069) at vibration damper bolt.
- Remove timing mechanism drive chain tensioner - arrows -.
- Remove bolt - arrow - and remove drive chain together with chain sprockets from intermediate shaft.
Installing
• Tightening specifications, refer to => [ Timing Chain Covers Assembly Overview ] Service and Repair, => [ Timing Chain Component Overview ] Timing Chain Component Overview.
- When reinstalling a used timing mechanism drive chain, note running direction marking - lower arrow -.
- Install drive chain together with large chain sprocket on intermediate shaft.
• Installation only possible in one position.
- If large chain sprocket cannot be installed, rotate intermediate shaft slightly.
- Check if crankshaft is in "TDC" position:
• Milled drive chain sprocket tooth must align with bearing joint - arrow A -.
• Tab on intermediate shaft sprocket must align with notch - arrow B - on intermediate shaft thrust washer.
- Install small chain sprocket on intermediate shaft.
• Installation only possible in one position.
- Replace the chain sprocket bolt for the intermediate shaft.
- Tighten chain sprocket bolt - arrow - by hand.
- Release locking splines in chain tensioner with small screwdriver - arrow -.
- Press tensioning rail against chain tensioner and tighten chain tensioner in this position - arrows -.
- Tighten chain sprocket bolt - arrow -.
- Counter hold with (T10069) at vibration damper bolt.
- Place the timing chain on the camshaft adjuster in such a way that the 2 individual copper color chain sprockets - CA - align with the markings on the camshaft adjuster. It is possible that the intake camshaft adjust will have to be rotated slightly.
- Mount the timing chain on the small chain sprocket. The marking - B - must align with the center copper color chain link - A -.
- Insert guide track - 1 - and tighten bolts - arrows -.
- Remove (T10068 A).
Risk of timing chain jumping off.
• If the crankshaft is rotated, forcefully press camshaft tensioning rail by hand (instead of with chain tensioner) against camshaft adjuster timing chain - arrow -.
- Rotate crankshaft 2 revolutions in direction of engine rotation at vibration damper bolt and place at "TDC" marking - arrow -.
- Cams - A - of cylinder 1 must face each other.
- At the same time, the (T10068 A) must engage in both shaft grooves.
• Marked links now take on an undefined position.
If the camshaft bar cannot be inserted:
- Repeat valve timing adjustment.
- Clean sealant residue from 3 mm bores - arrows - in cylinder head seal.
• With cylinder head installed, holes in cylinder head seal are only half visible.
- Check whether timing chain lower cover guide pins are inserted in cylinder block.
- Lightly coat clean sealing surfaces - shaded - on timing chain lower cover with sealant.
• Timing chain lower cover must be installed with 5 minutes of applying sealant.
- Remove lower timing chain cover bolts - arrow -.
- Fill 3 mm bores - arrows - in cylinder head seal with sealant.
• With cylinder head installed, holes in cylinder head seal are only half visible.
- Replace timing chain upper cover sealing ring. Refer to => [ Timing Chain Upper Cover Seal ] Timing Chain Upper Cover Seal.
- Check whether fitting sleeves - 2 - and - 3 - are inserted in upper timing chain cover.
- Insert new sealing ring - 1 - and new seal - 4 -.
- Lightly coat clean sealing surface - shaded - on timing chain upper cover with sealant.
- Coat sealing surface below cylinder head seal with some sealant. Do not bend cylinder head seal.
• Timing chain upper cover must be installed with 5 minutes of applying sealant.
- Position upper timing chain cover and tighten. Refer to => [ Upper Timing Chain Cover - Tightening Specifications
and Tightening Sequence ] Service and Repair.
- Install camshaft timing chain tensioner - arrow -.
- Rotate crankshaft 2 revolutions in direction of engine rotation at vibration damper bolt and place at "TDC" marking.
- Check timing again.
- Install crankshaft sealing ring. Refer to => [ Crankshaft Seal, Replacing ] Service and Repair.
- Install cylinder head cover. Refer to => [ Cylinder Head Cover ] Cylinder Head Cover
- Install intake manifold.
- Install coolant thermostat housing. Refer to => [ Coolant Thermostat Housing ] Coolant Thermostat Housing.
- Install oil pan => [ Installing ] Oil Pan.
- Install dual mass flywheel. Refer to => [ Dual Mass Flywheel ] Dual Mass Flywheel.
- Install engine. Refer to => [ Engine, Installing ] Engine, Installing.
- Fill engine oil and check oil level. Refer to => [ Oil Level, Checking ] Testing and Inspection.