Timing Chain: Service and Repair

11 31 051 - Replacing timing chain (N14)

Note:
This article has been updated by Technical Service Bulletin (TSB) M 11 02 10, dated April 2010

The final torque angle for tightening the Torsion Damper hub to crankshaft central bolt has been changed from 100° to 180°





Special tools required:





Important!
- Modified procedure for timing adjustment.
- The timing is not determined at firing TDC of cylinder no. 1.
- All pistons are in the 90° position.
- Observe direction of rotation (direction of rotation always clockwise when viewed towards timing drive side).





Necessary preliminary tasks:
- Remove cylinder head cover Service and Repair.
- Remove all spark plugs.
- Remove vibration damper Service and Repair.
- Remove chain tensioner Service and Repair.
- Remove VANOS adjustment unit Service and Repair.
- Remove sprocket wheel for exhaust camshaft.
- Remove PTFE ring Service and Repair at front.
- Remove belt tensioner [1][2]Replacing Tensioning Device for Alternator Drive Belt.
- Remove friction gear.





Position crankshaft with special tool 11 9 590.

Do not remove special tool 11 9 590 during repair work.





Move front panel into assembly position.

Suspend engine with engine crane (1) from lifting eye (2).





Remove adapter plate.

Remove right engine mount Replacing Right Engine Mount.





Note:
Do not remove alternator.

Release upper alternator bolts.

Secure special tool 11 9 630 with standard bolts (1 and 2).





Do not remove special tool 11 9 550.





Important!
Employ a second person for gripping when releasing central bolt (1).

Fit special tool 11 9 280 on hub for vibration damper with screws (2).

Release central bolt (1).





Release central bolt in direction of arrow.

Tightening torque: 11 21 1AZ Mechanical Specifications.





Release bearing pins (1 and 2).

Tightening torque: 11 31 6AZ Mechanical Specifications.





Remove hub (3) towards front.

Remove chain module with timing chain.

Using a hook (2), pull oil pump chain (1) upwards.





Sprocket wheel (1) of timing chain.

Sprocket wheel (2) of oil pump.





Secure chain module (1) with rubber (3) to facilitate assembly.

Pull timing chain (2) upwards until sprocket wheel (4) rests against chain guide (1).

Install timing chain (2) and sprocket wheel (4) in this position.

Installation Note:
Always keep timing chain (2) tensioned; it is possible for timing chain (2) to jam on chain module (1).





Installation position of both sprocket wheels.

Sprocket wheel (1) of oil pump.

Guide rail (2) of timing chain.

Hub (3) on crankshaft.

Sprocket wheel (4) of timing chain.





Attach oil pump sprocket wheel (2) in direction of arrow to crankshaft (1).

Insert chain module with timing chain and secure.

Attach crankshaft hub.

Screw in central bolt.





Remove special tool 11 9 280 from hub.

Secure central bolt with special tool 00 9 120.





Install VANOS adjustment unit Service and Repair.

Install sprocket wheel for exhaust camshaft.

Crank engine twice.

Check timing Adjustments.

Install PTFE ring Service and Repair.

Assemble engine.