Valve Timing, Adjusting
Valve Timing, Adjusting
Special tools, testers and auxiliary items required
• Torque Wrench (V.A.G 1331)
• Torque Wrench (V.A.G 1332)
• Securing pin (T03006)
• Multi-point socket (T10035)
• Counter-holder tool (T10172)
• Camshaft locator (T40070)
• 2 bolts M8x16
Modify Counterhold (T10172)
- Remove adapter (T10172/1) and screw in bolts - A - M8x16.
• The valve timing must be adjusted if the camshaft chain sprockets were loosened during repairs or if the valve timing is not set.
Secure camshafts if valve timing is correct
- Remove chain case cover => [ Chain Compartment Cover ] Chain Compartment Cover.
- Remove cylinder head cover => [ Cylinder Head Cover ] Service and Repair.
- Secure crankshaft for adjusting valve timing => [ Crankshaft, Locking to Check/Adjust Valve Timing ] Crankshaft, Locking to Check/Adjust Valve Timing.
- Install camshaft locator (T40070) as depicted on to camshafts and tighten bolts to 20 Nm.
If bolts could not be screwed in easily, attempt to rotate exhaust camshaft at recess using an open-end wrench - A - (18 mm or 19 mm, depending on wrench width) slightly in direction of - arrow - in order to eliminate any play in the chain drive.
- Relieve tension on timing chain. To do so, insert a screwdriver of appropriate size between piston of chain tensioner and tensioning track and press in direction of - arrow -.
- Secure completely pressed in piston using Locking Pins (T03006). Locking pin must be inserted until it stops.
Secure camshafts if valve timing is not correct
- Remove chain case cover => [ Chain Compartment Cover ] Chain Compartment Cover.
- Rotate crankshaft to TDC cylinder 5 => [ Crankshaft, Locking to Check/Adjust Valve Timing ] Crankshaft, Locking to Check/Adjust Valve Timing, however do not peg the crankshaft using locking pin (T40069).
- Rotate crankshaft so that camshaft locator (T40070 ) can be screwed easily on to camshafts as depicted.
- Tighten bolts of camshaft locator (T40070) to 20 Nm.
Remove chain sprockets of camshafts.
- Relieve tension on timing chain. To do so, insert a screwdriver of appropriate size between piston of chain tensioner and tensioning track and press in direction of - arrow -.
- Secure completely pressed in piston using drift ( T03006). Drift must be inserted until it stops.
- Remove bolts - 1 - and - 4 - using socket insert (T10035) and remove chain sprockets - 2 - and - 3 -.
If necessary, chain sprocket - 3 - must be pressed off lightly using a screwdriver.
• Secure crankshaft => [ Crankshaft, Locking ] Procedures if not yet secured. Crankshaft must only be rotated slightly around TDC point for this. Otherwise there is a risk the valves rest on the pistons.
Valve Timing, Adjusting
• Crankshaft secured by locking pin (T40069)
• Camshafts secured by camshaft locator (T40070)
• Chain tensioner is tensioned
- Place chain sprockets - 2 - and - 3 - as depicted into timing chain, attach them on to camshafts and screw in new bolts - 1 - and - 4 - hand-tight.
Chain gears must still be able to be rotated, however they must not tilt.
• Make sure that timing chain lies correctly in gliding and tensioning tracks.
- Relieve tension on chain tensioner by pressing in the piston and pulling out drift (T03006).
- Attach modified retainer (T10172) on to chain sprocket for exhaust camshaft - 4 -.
• A second technician is required for the following work steps.
- Hold timing chain at pre-load by pressing retainer (T10172) in direction of - arrow -.
- Simultaneously tighten bolt - 2 - of intake camshaft first and then bolt - 3 - of exhaust camshaft to 60 Nm.
Then tighten bolts - 2 - and - 3 - 90° (1/4 rotation) further.
• When applying the additional torque of 90°, timing chain must no longer be held at pre-load.
- Remove camshaft locator (T40070).
- Remove locking pin (T40069) for securing crankshaft.
- Rotate crankshaft 2 rotations in direction of engine rotation and secure it => [ Crankshaft, Locking to Check/Adjust Valve Timing ] Crankshaft, Locking to Check/Adjust Valve Timing, securing crankshaft for checking/adjusting valve timing.
- Check valve timing => [ Valve Timing, Checking ] Valve Timing, Checking.
If valve timing is not correct:
- Loosen chain sprockets of camshafts again and adjust valve timing again (replace camshaft bolts).
The rest of installation follows reverse of the removal procedures. When doing this note the following:
• Remove locking pin (T40069) from cylinder block at rear and screw in plug.
• Fill with coolant => [ Cooling System, Draining and Filling ] Cooling System, Draining and Filling.