Camshaft Timing Chains
Camshaft Timing Chains
Special tools, testers and auxiliary items required
• Crankshaft Holder (3242)
• Key (T40049)
• Adjusting Pin (T40060) (quantity: 2)
• Adapter (T40061)
• Adapter (T40062)
• Two 3.3 mm drill bits
Removing
• Transmission removed.
Risk of damaging valves and piston crowns.
• Turn the crankshaft and camshafts only with the chain drive completely installed.
- Remove timing chain lower cover. Refer to => [ Lower Timing Chain Cover ] Lower Timing Chain Cover.
- Attach the (T40049) to the back of the crankshaft using two old drive plate bolts - arrows -.
• The (T40060) has a flat part - 2 - which makes it easier to insert if the camshaft and the cylinder head are slightly offset.
• Insert the pin so that the bolt - 1 - is perpendicular to the camshaft axle.
• Move the bolt - 1 - 90° - arrow - so that it is perpendicular to the camshaft axle and it is possible to attain the correct Top Dead Center (TDC) position.
Components could be destroyed by the camshaft timing chain jumping off.
• Only rotate the crankshaft in the direction of engine rotation.
- Use the (T40049) to rotate the crankshaft to TDC:
- Check whether camshafts of both cylinder heads stand in TDC position.
• It must be possible to secure the camshafts with the (T40060).
• The bolt - arrow - in the (T40060) must be perpendicular to the center axle of the camshaft on cylinder bank 1 (right).
• The bolt - arrow - in the (T40060) must be perpendicular to the center axle of the camshaft on cylinder bank 2 (left).
- Remove the bolt - arrow - for the TDC marking from the upper section of the oil pan by using a long hex socket wrench with a ball head.
- Install the (3242) in the hole and tighten to 20 Nm. Turn the crankshaft - 1 - back and slightly to completely center the bolt, if necessary.
- To protect against cuts, wrap the point and the cutting edges on a 3.3 mm drill bit with insulating tape.
- Push the tensioning track of chain tensioner for the left camshaft timing chain in direction of - arrow - and secure the chain tensioner with a 3.3 mm drill bit - 1 -.
If the running direction is reversed on a used camshaft timing chain, it could be destroyed.
• Paint arrows to mark the timing chain running direction so it can be installed again.
- Remove the (T40060) from both camshafts.
- Remove the bolt - 3 - and remove the tensioning rail.
- Remove the bolts - 1 - for the guide rail and bolts - 2 - for the camshaft chain sprocket.
- Remove the camshaft chain sprocket, guide rail and left camshaft timing chain.
- To protect against cuts, wrap the point and the cutting edges on a 3.3 mm drill bit with insulating tape.
- Push the chain tensioner guide rail for the right camshaft timing chain in direction of - arrow - and secure the chain tensioner with a 3.3 mm drill bit - 1 -.
If the running direction is reversed on a used camshaft timing chain, it could be destroyed.
• Paint arrows to mark the timing chain running direction so it can be installed again.
- Remove the chain tensioner bolts - 1 - and camshaft chain sprocket - 3 - and bolts - 2 -.
- Remove the camshaft chain sprocket, chain tensioning and right camshaft timing chain.
Installing
• For the correct tightening specifications, refer to => [ Camshaft Timing Chains Overview ] Camshaft Timing Chains Overview.
• Secure crankshaft - 1 - in TDC position using (3242).
• Drive chain for timing mechanism installed. Refer to => [ Timing Mechanism Drive Chain ] Timing Mechanism Drive Chain.
• Replace bolts which have been tightened to an additional torque.
Risk of damaging valves and piston crowns.
• If camshafts are rotated, crankshaft may not rest with any piston at TDC.
- Check whether camshafts of both cylinder heads stand in TDC position.
• It must be possible to secure the camshafts with the (T40060).
• The bolt - arrow - in the (T40060) must be perpendicular to the center axle of the camshaft on cylinder bank 1 (right).
• The bolt - arrow - in the (T40060) must be perpendicular to the center axle of the camshaft on cylinder bank 2 (left).
- Remove the (T40060) from both camshafts.
Risk of damaging valves and piston crowns.
• If camshafts are rotated, crankshaft may not rest with any piston at TDC.
• If the camshafts are not secured, it is possible to correct them slightly with the (T40061) by installing the camshaft chain sprocket on the camshaft.
- Install the left camshaft timing chain with the camshaft chain sprocket, the guide rail and the tensioning rail.
• The slots in the camshaft chain sprocket must be at the middle position in relation to the threaded holes in the camshaft.
- Tighten the bolts - 1 - and - 3 - for the guide rail and the tensioning rail.
- Install both camshaft chain sprocket bolts - 2 - loosely.
• It must still be possible to rotate the camshaft chain sprocket on the camshaft and it must not tip.
- Secure the left camshaft with the (T40060).
• The bolt - arrow - in the (T40060) must be perpendicular to the center axle of the camshaft.
- Pull the drill - 4 - out of the alignment hole, thereby releasing the chain tensioner.
- Install the right camshaft timing chain with the chain sprocket and chain tensioner.
• The slots in the camshaft chain sprocket must be at the middle position in relation to the threaded holes in the camshaft.
- Tighten the chain tensioner bolts - 1 -.
- Install both camshaft chain sprocket bolts - 2 - loosely.
• It must still be possible to rotate the camshaft chain sprocket on the camshaft and it must not tip.
- Secure the right camshaft with the (T40060).
• The bolt - arrow - in the (T40060) must be perpendicular to the center axle of the camshaft.
- Pull the drill bit - 3 - out of the alignment hole, thereby releasing the right chain tensioner.
- Pre-tighten the right camshaft chain sprocket using the (T40062) and torque wrench to 20 Nm in direction of - arrow - and hold.
- Fasten bolts - 1 - and - 2 -.
- Remove the adapter (T40062) and (T40060).
- Tighten the remaining bolts for the right camshaft chain sprocket.
- Pre-tighten the left camshaft chain sprocket using the (T40062) and torque wrench to 15 Nm in direction of - arrow - and hold.
- Fasten bolts - 1 - and - 2 -.
- Remove the (T40062) and (T40060).
- Tighten the remaining bolts for the left camshaft chain sprocket.
- Remove the (3242).
Checking the Valve Timing
Components could be destroyed by the camshaft timing chain jumping off.
• Turn crankshaft only in direction of engine rotation - arrow -.
- Turn the crankshaft 2 turns using the (T40049) until it is just in front of TDC.
- Lock the crankshaft - 1 - from turning using the (3242) to 20 Nm.
An inaccurate TDC setting will cause an inaccurate setting.
• If the crankshaft was turned past TDC: Turn the crankshaft again 2 turns until it is just in front of TDC, then lock it from moving with the (3242).
- Check whether camshafts of both cylinder heads stand in "TDC" position.
• It must be possible to secure the camshafts with the (T40060).
• The bolt - arrow - in the (T40060) must be perpendicular to the center axle of the camshaft on cylinder bank 1 (right).
• The bolt - arrow - in the (T40060) must be perpendicular to the center axle of the camshaft on cylinder bank 2 (left).
Correcting the Valve Timing
- If one of the camshafts does not lock, loosen all the bolts - arrows - for that particular camshaft chain sprocket about 1 turn.
- Mount the (T40061) over the bolt heads.
- Turn the camshaft by the (T40061) just a little back and forth until it is possible to insert the (T40060).
• The bolt - arrow - in the (T40060) must be perpendicular to the center axle of the camshaft.
- Tighten the bolts for the camshaft chain sprocket with the (T40061) and the (T40060) still attached to approximately 5 Nm.
- Remove the (T40060) and (T40061).
- Tighten the camshaft chain sprocket bolts to final torque.
- Repeat the procedure on the other cylinder bank if necessary.
- Remove the (3242).
- Check the valve timing once again.
The rest of the installation is performed in reverse order of removal, noting the following:
- Tighten the bolt for the TDC marking in the upper section of the oil pan. Refer to => [ Upper Oil Pan Overview ] Upper Oil Pan Overview.
- Install timing chain lower cover. Refer to => [ Lower Timing Chain Cover ] Lower Timing Chain Cover.
- Fill engine oil and check oil level.