Setting Timing For Camshafts
Incorrect handling of crankshafts
- Risk of damage to the timing system
→ Never turn the crankshaft against the rolling direction or when the chain tensioner is removed.
→ Proceed carefully with your work.
→ Only turn the engine at the crankshaft.
→ Observe general warning notes and working regulations.
Timing not set correctly
- Risk of engine damage
- Rough running engine
- Loss of engine power
→ Do not use force when fitting the staking tool.
→ Make sure that the gap is equal on both sides.
→ When inserting the staking tools, do not use force to turn the camshafts against any resistance.
→ The engine must be exactly at top dead centre.
→ The opposite cylinder must be at ignition TDC.
- Turn the crankshaft at the vibration balancer using > 9714 - socket-wrench insert so that the staking bore of the vibration balancer -2-
is approx. 45 degrees in front of the lower staking point on timing-case cover -1-
.
Staking bore 45 degrees in front of overlapping TDC of cylinder 1
- Loosen camshaft controller and sprockets on the four camshafts just until they can turn freely (no wobbling). Always counter at the hexagon on the components when doing this. > Sprocket
> Camshaft controller
Sprocket
Camshaft controller
- Unscrew and remove engine chain tensioner.
> 153619 REMOVING AND INSTALLING CHAIN TENSIONER
Place cloths underneath to catch drops of oil.
- Screw in assembly chain tensioner > 9683/1 - auxiliary chain tensioner by hand. Connect 1 bar of compressed air and slowly increase to 5.0 up to 5.5 bar (prevents the assembly chain tensioner from "crashing" against the control chain). -Arrow-
Assembly chain tensioner
- Turn the four camshafts at the hexagon using an open-ended wrench until both > 9678/1 - staking tools can be fitted uniformly at the same time on the side edges (dihedron) of the two intake and outlet camshafts in question between cylinders 3/4 and 7/8. For information on possible errors, see above (section on "Information").
Hexagon at camshaft
- 5.1 Position the staking tool according to the section above entitled "Correct setting and possible errors".
- 5.2 Position the staking tool over the side edges of the two camshafts in such a way that the narrow end of the side edges of the camshafts points upwards to the staking tool. When positioning the staking tool, take into consideration the structural difference in height of the camshafts in the cylinder head. Turn the staking tool if necessary.
- 5.3 Carefully turn the camshafts at the hexagon using an open-ended wrench until the staking tool can be fitted over the side edges. Then carefully turn the camshafts alternately back and forth at the hexagon > Turning camshafts while mounting tool
and slowly and carefully tighten the valve cover screws at the staking tool. When doing this, check that the staking tool protrudes at the same distance from the cylinder head on both sides (visual inspection with torch). Depending on the production tolerance, the staking tool may lie directly on the cylinder head or there may be a small gap. Everything is fixed correctly when the staking tool is fitted uniformly and there is no longer any play in the camshaft when the hexagon is turned.
Turning camshafts while mounting tool
Uniform mounting on camshafts
Staking tool screwed uniformly on cylinder head
- 5.4 Set other cylinder bank in the same way (fix camshafts).
- 5.5 Now all four camshafts are fitted uniformly and without play with both staking tools. When you inspect the camshafts with the torch, you can see no apparent gap between the side adjustment edges of the camshafts and the staking tool.
- Insert staking pin > 9595/1 - locating pins into the staking bore on the vibration damper -2-
.
Due to space constraints, a screw (M8 x 50-65) can also be used instead of staking pin 9595/1.
For example: Part No.: 900.385.071.01 screw, M8 x 50, or 999.073.411.01 screw, M8 x 60.
Staking bore in vibration damper
- Turn the crankshaft at the vibration damper in such a way -3-
that the staking pin in the vibration balancer slips into the lower staking point on timing-case cover -1-
. At the same time, exert gentle pressure on the staking pin while turning.
Staking position in timing-case cover
- If you accidentally turn the vibration damper too far, do not try to turn it back again! The staking tools must be removed and the camshafts must be turned in such a way that there is only the slightest pressure on the valve springs. Turn the crankshaft once and start the setting procedure again.
- Camshafts and crankshaft are fixed correctly.
Fitted tools
1 Screwed-in assembly chain tensioner with approx. 5.0 to 5.5 bar pressure. 2 Two fixed staking tools on the camshafts. 3 Staking pin secures crankshaft in TDC of cylinder 1. Information
The tightening specifications for the basic engine are stored centrally.
/
or
> WM, 1001IN TIGHTENING TORQUES, TIGHTENING SEQUENCES, ASSEMBLY OVERVIEWS FOR ENGINE
Tightening torques and assembly instructions for other assemblies (e.g. chassis, electrics, transmission or body) or for peripheral engine equipment can be found in the corresponding documents.
- Screw down camshaft controller and sprockets on the four camshafts as instructed. Always counter at the hexagon on the components when doing this. > Sprocket
> Camshaft controller
Observe the following sequence =>
- Sprocket on cylinders 1 to 4 for outlet camshaft
- Camshaft controller on cylinders 1 to 4 for intake camshaft
- Camshaft controller on cylinders 5 to 8 for intake camshaft
- Sprocket on cylinders 5 to 8 for outlet camshaft
Sprocket
Camshaft controller
Camshaft adjustment
1 M12 screw Tighten fully after setting valve timing! 2 Camshaft controller with integrated hexagon for countering 3 Hydraulic valve for camshaft adjustment (NVS) 4 M5 x 12 screw Control chain and sprockets
1 Double-chain camshaft drive 2 Camshaft sprocket with integrated hexagon for countering 3 M12 screw Tighten fully after setting valve timing! 4 Deflector rail 5 M8 x 35 screw 6 Camshaft-to-camshaft guide pad A Direction of travel - Remove tools.
- Fit chain tensioner.