LEMON Manuals: Even more car manuals for everyone
Home >> BMW >> 2011 >> 535i GT >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine - Repair >> Variable Valve Gear >> 11 37... Fault patterns, valve gear (N20/26 / N55)

11 37... Fault patterns, valve gear (N20/26 / N55)

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.

The eccentric shaft has mounting flats on both sides;  if the engine is installed, the front mounting flat must be used.

Heed the following work instructions.

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

Fig 1: Turning Eccentric Shaft On Mounting Flats Using Open-End Spanner
G08419877Courtesy of BMW OF NORTH AMERICA, INC.

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

Check throttle return spring (2) for breakage and correct installation position on intermediate lever (1).

Check roller cam follower (3) for correct installation position.

Fig 2: Identifying Throttle Return Spring, Intermediate Lever And Roller Cam Follower
G04725590Courtesy of BMW OF NORTH AMERICA, INC.

Check that intermediate lever (1) is correctly seated.

NOTE: Graphic does not show sliding block.
Fig 3: Identifying Intermediate Lever
G08419879Courtesy of BMW OF NORTH AMERICA, INC.

Check wear at stop (1) - minimum lift and maximum lift.

Check that stops are securely seated.

Tightening torque: 11 37 5AZ .

Fig 4: Identifying Stop
G08419880Courtesy of BMW OF NORTH AMERICA, INC.

Stiff movement in eccentric shaft bearing is excluded.

Stiff movement can occur in worm gear.

Fig 5: Identifying Stiff Movement In Eccentric Shaft Bearing
G08419881Courtesy of BMW OF NORTH AMERICA, INC.

Assemble engine.

scientia non olet · About LEMON Manuals