Removing and Installing / Replacing Inlet and Exhaust Adjustment Units on Left Side

Removing and Installing / Replacing Inlet and Exhaust Adjustment Units on Left Side (N62/N62TU)


Special Tools Required:

11 9 190
11 9 460
11 9 461
11 9 462
11 9 463

Cylinder Bank 5 to 8

Necessary Preliminary Tasks:
- Read fault memory and make a documentary record
- Remove servomotor for left eccentric shaft
- Remove left cylinder head cover
- Remove all spark plugs on cylinder bank 5 to 8
- If necessary, remove fan cowl
- Remove left timing case cover

Removal:

Removal of inlet and exhaust adjustment unit is described separately from installation.







Important!
Screw ( 1 ) is a special screw and must not be replaced with a normal M8 screw.

Release screw ( 1 ).

Unclip oil line ( 3 ) from retainers ( 2 ) and remove.

Crank engine at central bolt in direction of rotation to firing TDC position of 1st cylinder.







Note:
With 1st cylinder in firing TDC position, cams of inlet and exhaust camshafts at 5th cylinder point upwards at an angle as shown in graphic.







Note:
Alignment hole for TDC position is at front on timing case cover.

Crank engine at central bolt and secure vibration damper with special tool 11 9 190 in firing TDC position of 1st cylinder.

Important!
When the engine is shut down, the inlet and exhaust adjustment unit is normally locked in its initial position.
The situation may arise in some individual cases where this initial position is not reached and the camshaft can continue to be rotated in the adjustment range of the adjustment unit.
In order to avoid incorrect timing adjustment, it is essential to check the locking of the adjustment unit and if necessary perform locking by rotating the camshafts.

Checking locking of inlet adjustment unit in initial position:







Engage hexagon head of inlet camshaft and attempt to rotate inlet camshaft carefully against direction of rotation.

If there is no fixed connection between inlet camshaft and inlet adjustment unit, rotate inlet camshaft against direction of rotation as far as it will go.

The inlet adjustment unit is locked in the initial position when the inlet camshaft is non-positively connected to the inlet adjustment unit.


Checking locking of exhaust adjustment unit in initial position:







Engage hexagon head of exhaust camshaft and attempt to rotate exhaust camshaft carefully in direction of rotation.

If there is no fixed connection between exhaust camshaft exhaust adjustment unit, rotate exhaust camshaft in direction of rotation as far as it will go.

The exhaust adjustment unit is locked in the initial position when the exhaust camshaft is non-positively connected to the exhaust adjustment unit.

Important!
If the inlet or exhaust adjustment unit of the camshafts "cannot" be locked as described, the adjustment unit is faulty and must be replaced.


Remove special tool 11 9 190.







Crank engine at central bolt against direction of rotation to 45° before TDC position.

Note:
When slackening screws, grip camshafts at hexagon head.







Slacken screws of exhaust and inlet adjustment unit.







Remove screw on exhaust adjustment unit.







Vigorously press back tensioner rail ( 3 ) several times to remove oil in chain tensioner.

Feed out exhaust adjustment unit ( 2 ).







Remove screw on inlet adjustment unit.







Feed out inlet adjustment unit ( 1 ).
Secure timing chain to prevent it from sliding down.


Installation:

Installation of inlet and exhaust adjustment units is described separately from removal.







Important!
Danger of mix-up:

Inlet and exhaust adjustment units are different.

Mixing up the inlet and exhaust adjustment units will cause damage to the engine.

1. Inlet adjustment unit ( 1 ) is marked with EIN and IN.

2. Exhaust adjustment unit ( 2 ) is marked with AUS and EX.

Note:
Position of inlet adjustment unit ( 1 ) to timing chain can be freely selected.

Pull timing chain up.







Feed inlet adjustment unit ( 1 ) into timing chain and fit onto inlet camshaft.







Replace screw.

Install screw on inlet adjustment unit.

Tighten screw without play and then slacken off again by half a turn.







Note:
Position of exhaust adjustment unit ( 2 ) to timing chain can be freely selected.

Pull timing chain up.

Feed exhaust adjustment unit ( 2 ) into timing chain.

Press tensioner rail ( 3 ) back and fit exhaust adjustment unit ( 2 ) onto exhaust camshaft.

Note:
If tensioner rail ( 3 ) cannot be pressed back far enough to enable fitting of exhaust adjustment unit ( 2 ):

Remove chain tensioner.

Place chain tensioner on a level surface and compress slowly and carefully.

Repeat this procedure twice.

Installation:

Replace sealing ring.

Install chain tensioner and tighten down.

Tightening torque of chain tensioner: 65 Nm.

Fit exhaust adjustment unit ( 2 ).







Replace screw.

Install screw on exhaust adjustment unit.

Tighten screw without play and then slacken off again by half a turn.







Get special tool kit 11 9 460 ready for securing camshafts.

Note:

Special tool 11 9 461 for securing inlet camshaft.

Special tool 11 9 462 for securing exhaust camshaft.

Special tool 11 9 463 ( holder with screw ).







Place special tool 11 9 461 on inlet camshaft and align inlet camshaft so that special tool 11 9 461 rests without a gap on cylinder head.







Fit special tool 11 9 463, secure screw ( 1 ) in thread for oil line and tighten down by hand.

Important!

Make sure screws of inlet and exhaust adjustment units have been slackened by a half a turn.







Crank engine at central bolt from 45° before TDC position in direction of rotation to firing TDC position of 1st cylinder.

Secure vibration damper with special tool 11 9 190 in firing TDC position of 1st cylinder.







Note:
When tightening down screw ( 1 ), grip camshaft at hexagon head.

Tighten down screw ( 1 ) of inlet adjustment unit.

Tightening torque of inlet adjustment unit: 80 Nm.







Release screw ( 1 ) and remove special tools 11 9 463 / 11 9 461 from inlet camshaft.







Place special tool 11 9 462 on exhaust camshaft and align exhaust camshaft so that special tool 11 9 462 rests without a gap on cylinder head.







Fit special tool 11 9 463, secure screw ( 1 ) in thread for oil line and tighten down by hand.







Note:
When tightening down screw ( 2 ), grip camshaft at hexagon head.

Tighten down screw ( 2 ) of exhaust adjustment unit.

Tightening torque of exhaust adjustment unit: 80 Nm.







Release screw ( 1 ) and remove special tools 11 9 463 / 11 9 462 from exhaust camshaft.







Remove special tool 11 9 190.

Crank engine at central bolt twice in direction of rotation until engine returns to firing TDC position of 1st cylinder.

Secure vibration damper with special tool 11 9 190 in firing TDC position of 1st cylinder.

Place special tool 11 9 461 on inlet camshaft and check timing.

Note:
The timing is correctly adjusted when special tool 11 9 461 rests flat on the cylinder head or protrudes by up to 0.5mm to the exhaust side.







Remove special tool 11 9 461 from inlet camshaft.







Place special tool 11 9 462 on exhaust camshaft and check timing.

Note:
The timing is correctly adjusted when special tool 11 9 462 rests flat on the cylinder head or protrudes by up to 0.5 mm to the exhaust side.

Remove all special tools.







Important!

Screw ( 1 ) is a special screw and must be replaced with a normal M8 screw.

Clip oil line ( 3 ) into retainers ( 2 ).

Insert screw ( 1 ) and tighten down.

Assemble engine.