LEMON Manuals: Even more car manuals for everyone
Home >> BMW >> 2017 >> X3 sDrive28i >> Repair and Diagnosis >> External Pages >> Different car >> Section 372 (Engine - Repair) >> Variable Valve Gear >> 11 37 020 Removing and installing/replacing servomotor for eccentric shaft (N55)

11 37 020 Removing and installing/replacing servomotor for eccentric shaft (N55)

WARNING: This page is about a different car, the 2013 BMW X5, 2012 BMW X5, and 2011 BMW X5. However, it is still accessible from the selected car via links, so may be relevant.
WARNING: The preloading on the throttle return springs increases as the rotation on the worm gear increases. Danger of injury! 
The eccentric shaft may only be twisted on the mounting flats for protection.
Risk of damage to the eccentric shaft gearing and to the servomotor worm drive.
The eccentric shaft must not  spring back to the minimum stroke stop. Risk of damage! 

Necessary preliminary tasks: 

WARNING: Heed stop installation instructions.

The eccentric shaft on the mounting flats (2) must only be turned with an open-end spanner (1) for support.

Heed the following work instructions.

After the motor stops, the eccentric shaft is in the maximum stroke position.

If the actuator drive is defective, the eccentric shaft is located in an undetermined position.

Fig 1: Identifying Mounting Flats & Open-End Spanner
G09953820Courtesy of BMW OF NORTH AMERICA, INC.

Release bolt (1) on the oil spray nozzle.

Tightening torque: 11 37 4AZ .

Unclip oil spray nozzle (2) from the bracket on the actuator drive (3) in direction of arrow.

Fig 2: Identifying Oil Spray Nozzle, Actuator Drive & Bolt
G09953821Courtesy of BMW OF NORTH AMERICA, INC.

If the eccentric shaft is not on maximum stroke, the eccentric shaft must be adjusted to maximum stroke.

IMPORTANT: Fix eccentric shaft with an open-end spanner (kickback danger)
Adjust eccentric shaft only on the hexagon socket of the actuator drive (preload).

Remove minimum stroke stop (1).

Fig 3: Removing Minimum Stroke Stop
G09953822Courtesy of BMW OF NORTH AMERICA, INC.

Turn 4-mm hexagon socket wrench (1) clockwise in direction of arrow (maximum stroke).

Secure eccentric shaft with an open-end spanner (2) for support in direction of arrow.

Fix eccentric shaft with an open-end spanner (2) (kickback danger)

Fig 4: Fixing Eccentric Shaft Using Open-End Spanner For Support
G09953823Courtesy of BMW OF NORTH AMERICA, INC.

Remove minimum stroke stop (1).

Tightening torque: 11 37 5AZ .

Fig 5: Identifying Minimum Stroke Stop
G09953824Courtesy of BMW OF NORTH AMERICA, INC.

Adjust eccentric shaft (1) to minimum stroke in direction of arrow via servomotor.

IMPORTANT: Secure eccentric shaft with an open-end spanner (kickback danger)
Fig 6: Adjusting Eccentric Shaft To Minimum Stroke
G09953825Courtesy of BMW OF NORTH AMERICA, INC.

Slowly adjust eccentric shaft in direction of arrow to minimum stroke via the servomotor with a 4-mm hexagon socket wrench (2) and an open-end spanner (1).

IMPORTANT: Secure eccentric shaft with an open-end spanner (1) (kickback danger)

Release gearing of the eccentric shaft from worm drive.

Fig 7: Securing Eccentric Shaft Using Open-End Spanner
G09953826Courtesy of BMW OF NORTH AMERICA, INC.
IMPORTANT: Eccentric shaft (2) is no longer connected to the worm drive of the servomotor in this working position.

Turn eccentric shaft (2) approximately 90° further with an open-end spanner (1).

Secure eccentric shaft (2) against kickback with the assistance of a second person.

Fig 8: Identifying Mounting Flats & Open-End Spanner
G09953827Courtesy of BMW OF NORTH AMERICA, INC.
IMPORTANT: Eccentric shaft (1) is located in a relaxed position.
Secure eccentric shaft (1) against kickback with the assistance of a second person.

Unfasten screws (2).

Fig 9: Identifying Eccentric Shaft With Screws
G09953828Courtesy of BMW OF NORTH AMERICA, INC.

Remove servomotor (1) upward in direction of arrow.

Installation note: 

Clean blind holes with compressed air.

Install servomotor (1) downward in direction of arrow.

Secure eccentric shaft against kickback with the assistance of a second person.

Installation note: 

The gearing of the eccentric shaft and the worm gear must be greased with LONGTIME PD 1 (4.1) .

Fig 10: Removing Servomotor Upward
G09953829Courtesy of BMW OF NORTH AMERICA, INC.

Installation note: 

Eccentric shaft and worm drive must now be joined.

Carefully mate eccentric shaft gear in the worm shaft of the servomotor by simultaneously pressing and turning on the actuator drive.

Insert bolts (2).

Tightening torque: 11 37 3AZ .

Fig 11: Identifying Eccentric Shaft Bolts
G09953830Courtesy of BMW OF NORTH AMERICA, INC.

Preload eccentric shaft to maximum stroke with a 4-mm hexagon socket wrench (1) on the servomotor in direction of arrow.

Fix eccentric shaft with an open-end spanner (2) for support and secure (kickback danger).

Fig 12: Fixing Eccentric Shaft Using Open-End Spanner For Support
G09953831Courtesy of BMW OF NORTH AMERICA, INC.

Adjust eccentric shaft (1) back to maximum stroke in direction of arrow via servomotor.

IMPORTANT: Fix eccentric shaft with an open-end spanner and secure. (kickback danger)
Fig 13: Adjusting Eccentric Shaft Back To Maximum Stroke
G09953832Courtesy of BMW OF NORTH AMERICA, INC.

Screw in stop (1) for minimum stroke.

Tightening torque: 11 37 5AZ .

IMPORTANT: Fix eccentric shaft with an open-end spanner and secure. (kickback danger)
Fig 14: Identifying Stop For Minimum Stroke
G09953833Courtesy of BMW OF NORTH AMERICA, INC.

Retract oil spray nozzle (2) on actuator drive (3).

Engage bolt (1) and release back to 90°.

For exact positioning of the oil spray nozzle (2) audibly clip it in at the top.

Secure oil spray nozzle (2) with screw (1).

Tightening torque: 11 37 4AZ .

Fig 15: Identifying Oil Spray Nozzle, Actuator Drive & Bolt
G09953834Courtesy of BMW OF NORTH AMERICA, INC.

Remove all special tools.

Assemble engine.

Check function of Digital Engine Electronics.