Variable Valve Timing Actuator: Service and Repair

11 36 010 Removing and installing, sealing/replacing VANOS adjustment unit (S54)

Special tools required:
- 11 5 100
- 11 6 050
- 11 7 130
- 11 7 200
- 12 6 050
- 12 6 410
- 12 6 411

Important! When the engine is switched off, VANOS moves the camshafts to a position which is advantageous to engine starting.
The camshafts and the VANOS adjustment unit must be placed in the installation position before the VANOS adjustment unit is removed.

Necessary preliminary tasks:
- Read fault memory and make a documentary record.
- Perform VANOS test.
- Remove cylinder head cover Service and Repair
- Remove all spark plugs.
- Remove fan clutch with impeller and fan cowl (not from E85). Service and Repair
- Disconnect fuel rail.





Unscrew screws (1). Remove sliding rail (2). Unscrew screws (3). Remove holder (4).
Important! Bolts can fall into the engine.





Disconnect plug connection on solenoid valve.
Connect special tools 12 6 050 and 12 6 411 to correct terminals on car battery.





Actuate starter motor for approx. 20-30 secs.; to do so, press buttons 1 and 3 alternately on special tool 12 6 050.

Important! Do not press and hold down buttons 1 and 3 permanently.

Press buttons 1 and 3 in short intervals.
Inlet and exhaust VANOS are retracted.





Crank engine at central bolt in direction of engine rotation.
If necessary, attach engine with special tool 11 5 100 to four bolts of crankshaft hub.





Rotate crankshaft in direction of rotation up to cylinder 1 firing TDC position.





Note: TDC allocation above marking on vibration damper is sufficient.





Detach bracket of oil line from timing case cover.





Remove oil line from VANOS adjustment unit.





Release screws on VANOS adjustment unit.





Important! Insert two M6x60 bolts (1) to avoid damaging the VANOS adjustment units.

Pull VANOS adjustment unit (2) towards front.

Note: In individual cases, an air cushion may form in the VANOS adjustment unit.

If necessary, ventilate with special tool 11 6 050.





Ventilate VANOS adjustment unit.
1 Press buttons 2 and 4 on special tool 12 6 050 simultaneously. The solenoid valves are activated and the oil chamber of the hydraulic piston is ventilated.
2 Pull off VANOS adjustment unit towards front.





Important! CCW thread!

Grip on dihedron (1) and release at hexagon (2).





Lever out pressure control valve (1) with pliers in direction of arrow (E85 only).
Grip on dihedron (2) and release at hexagon (3) of inlet VANOS.
Grip on dihedron (5) and release at hexagon (6) of exhaust VANOS.
Remove two M6x60 bolts.





Remove VANOS adjustment unit towards front.
Feed out VANOS adjustment unit towards top (E85 only).

Note: The toothed shafts (1) remain in the VANOS gear on the engine.

Important! The engine must not be cranked while the VANOS adjustment unit is removed. The toothed shafts may move and slip out of the toothing. The frictional connection of the camshafts will be cancelled, and the valves could be exposed at the piston, or the timing must be readjusted.

E85 only:



Installation:
For installation of VANOS adjustment unit in installed engine.

Attach special tool 11 7 130 and connect a compressed air supply of 2 to 8 bar.
Briefly actuate buttons 1 and 3 on special tool 11 6 050.
Both radial pistons (1) on VANOS adjustment unit must be retracted (retarded setting).





Setting of radial pistons (1) on VANOS adjustment unit.





Note: A filter is integrated in the control valve.

In the event of engine damage which suggests that the filter is contaminated with swarf/chips, it is essential to replace the control valve.
Replace sealing rings (1) and coat with oil as antiseize agent.
Preassemble control valve in cylinder head.





Check dowel sleeves (1) for damage and correct installation position.





Replace seal (1).

Important! Note direction of installation of gasket.

Install gasket (1) in such a way that beading points to VANOS adjustment unit.
Secure gasket (1) with sealing compound on adapter sleeves.





Place VANOS adjustment unit on toothed shafts (1).





Insert M6x60 bolts (1).
Attach special tool 11 7 130 and connect a compressed air supply of 2 to 8 bar.
Briefly actuate buttons 2 and 4 on special tool 11 6 050.
Both axial pistons (4 and 5) on the VANOS adjustment unit must now be extended (advanced setting).





Important! CCW thread!

Grip on dihedron (1) and screw in at hexagon (2).
Grip on dihedron (1) and screw together at hexagon (2) alternately between exhaust and inlet sides in 1/2 turn increments.
Secure union nut (2) with special tool 11 7 200.
Tightening torque 10 Nm.





Align radial piston pump to driver on spline hub.
Note: Picture shows a schematic representation.





Press buttons 1 and 3 on special tool 12 6 050 simultaneously. The solenoid valves are activated and the air can escape from the hydraulic pistons of the VANOS adjustment unit.
Simultaneously push on VANOS adjustment unit until it rests on cylinder head.

Important! If this position is not reached, check position of radial piston pump to driver and realign if necessary.





Insert screws of VANOS adjustment unit and tighten down.





Note: Check installed direction.

Install holder (4).





Insert screws (3) and secure holder (4) (do not tighten down screws (3) yet)
Install sliding rail (2).
Insert screws (1).
Tighten down screws (1) and screws (3).





Disconnect special tool 12 6 050 and special tool 12 6 410 and remove.
Insert screw connections in solenoid valves.





Replace sealing rings of banjo bolt.
Insert banjo bolt but do not tighten down yet.





Install bracket of oil line. Install screw and tighten down.





Tighten down banjo bolt of oil line.
Tightening torque 11 36 9AZ.

Assemble engine.

There is air in the VANOS system once it is opened.
In the first few seconds after startup this results in a clearly discernible "rattling noise".
This rattling noise does "not" indicate incorrect assembly.
The rattling noise will disappear as soon as the oil pressure has built up and the system has vented.

Perform VANOS test.