Removing and Installing/Replacing Intermediate Levers
11 37 010 - Removing and installing/replacing intermediate levers (N52)
Special tools required:
- 11 4 270 11 4 270 Removal and Mounting Fixture
- 11 4 450 11 4 450 Locating Fixture
- 11 4 481 11 4 480 Placement Boards (2 X)
Important!
Aluminium-magnesium materials.
No steel screws/bolts may be used due to the threat of electrochemical corrosion.
A magnesium crankcase requires aluminium screws/bolts exclusively.
Aluminium screws/bolts must be replaced each time they are released.
Aluminium screws/bolts are permitted with and without
color coding (blue).
For reliable identification:
Aluminium screws/bolts are not magnetic.
Jointing torque and angle of rotation must be observed without fail (risk of damage).
Necessary preliminary tasks:
- Remove cylinder head cover Service and Repair.
If necessary, set eccentric shaft (1) on twin surface to minimum lift (2).
Secure special tool 11 4 270 11 4 270 Removal and Mounting Fixture with gripping pliers (3) to guide block (2).
Important!
Special tool 11 4 270 11 4 270 Removal and Mounting Fixture is only secured to guide block.
Adjusting the gripping pliers (3) is not permitted (risk of damage) on special tool 11 4 270 11 4 270 Removal and Mounting Fixture.
Note:
The oil nozzle must be removed beforehand from cylinder no. 3.
Warning!
Risk of injury in event of incorrect use.
Important!
Incorrect handling risk of damage.
Secure both bearing pins (2) in return spring with knurled screw (1) on special tool 11 4 270 11 4 270 Removal and Mounting Fixture.
Press special tool 11 4 270 11 4 270 Removal and Mounting Fixture in direction of arrow as far as it will go.
Release steel screw (2).
To avoid jamming with screw (2) and return spring, it is necessary when releasing screw (2) to relieve the pretension on special tool 11 4 270 11 4 270 Removal and Mounting Fixture uniformly.
Important!
Risk of damage to cylinder head thread.
Tightening torque: 11 37 2AZ 11 37 Variable Valve Gear.
Relieve tension on return spring (1) with special tool 11 4 270 11 4 270 Removal and Mounting Fixture.
Note:
Metal lug (2) cannot be disassembled and must not be removed.
Installation Note:
Replace metal lug if tab washer is defective.
Press return spring apart at position (1) and remove towards top.
Important!
Uniform distribution must not be changed.
All components must be set down in a clean and orderly fashion.
All components must be reinstalled in the same positions in an engine which has already been in use.
1 - Eccentric shaft with bearing
2 - Bearing caps of eccentric shaft set out in order.
3 - Inlet camshaft
4 - Bearing caps of inlet camshaft set out in order.
5 - Intake valves with valve springs
6 - Valve plates and valve cotters
7 - Roller cam followers with HVC element set out in order.
8 - Return springs.
9 - Guide blocks set out in order.
10 - Intermediate levers set out in order.
Release screws (1).
Tightening torque: 11 37 1AZ 11 37 Variable Valve Gear.
Set down guide blocks (2) in special tool 11 4 481 11 4 480 Placement Boards (2 X) in neat order.
Installation Note:
Mixing up the guide blocks may cause the engine to demonstrate idle fluctuations.
This will result in maladjustment of uniform distribution.
Installation Note:
Contact surfaces (1) must be clean and oil-free.
Clean if necessary.
Lift out intermediate levers (2).
Intermediate levers (2) set out in special tool 11 4 481 11 4 480 Placement Boards (2 X) in order.
Installation Note:
Mixing up the intermediate levers may cause the engine to demonstrate rpm fluctuations.
Installation Note:
Contact surfaces (1) must be clean and oil-free.
Clean if necessary.
All intermediate levers (1) are classified.
Reinstall intermediate levers which have already been used in the same positions.
Installation Note:
Before reinstalling the intermediate levers, make sure the roller cam followers are correctly positioned (risk of damage).
Install intermediate levers (2).
Fit guide block (2) cleanly into opening.
Tighten screws (1) hand-tight.
Check both intermediate levers again to ensure correct installation position.
Release bolts (1) again by a 1/4 turn.
Secure special tool 11 4 450 11 4 450 Locating Fixture to bolt connection (1) of eccentric shaft.
Turn eccentric lever (3) on special tool 11 4 450 11 4 450 Locating Fixture in direction of arrow.
Guide block is now tensioned.
Secure screws (2).
Tightening torque: 11 37 1AZ 11 37 Variable Valve Gear.
Installation Note:
At cylinder no. 3, the guide block can be pre-installed with one bolt (2) only.
Fit oil pump only after retaining spring has been fitted.
Fit return spring on guide block.
Installation Note:
Insert return spring (2) in intermediate lever (1) (see arrow).
Check roller cam follow (3) again to ensure correct installation position.
Secure special tool 11 4 270 11 4 270 Removal and Mounting Fixture with gripping pliers (3) to guide block (1).
Important!
Special tool 11 4 270 11 4 270 Removal and Mounting Fixture is only secured to guide block.
Adjusting the gripping pliers (3) is not permitted (risk of damage) on special tool 11 4 270 11 4 270 Removal and Mounting Fixture.
Warning!
Risk of injury in event of incorrect use.
Important!
Incorrect handling risk of damage.
Secure both bearing pins (2) in return spring with knurled screw (1) on special tool 11 4 270 11 4 270 Removal and Mounting Fixture.
Important!
Check return spring again on intermediate lever to ensure correct installation position.
Press special tool 11 4 270 11 4 270 Removal and Mounting Fixture in direction of arrow as far as it will go.
Insert steel screw (2).
To avoid jamming with screw (2) and return spring, it is necessary when inserting screw (2) to increase the pretension on special tool 11 4 270 11 4 270 Removal and Mounting Fixture uniformly.
Important!
Risk of damage to cylinder head thread.
Tightening torque: 11 37 2AZ 11 37 Variable Valve Gear.
Remove special tool 11 4 270 11 4 270 Removal and Mounting Fixture.
At cylinder no. 3, adjust oil nozzle (2) exactly so that oil spray (3) points precisely towards spline teeth.
Assemble engine.