11 31 090 Installing and removing/replacing chain tensioner piston (N20)

WARNING: This page does not describe the selected car, but rather 50 other vehicles, including the 2016 BMW M5, 2016 BMW ActiveHybrid 5, 2016 BMW 550i xDrive, 2016 BMW 550i, and 2016 BMW 535i xDrive. However, it is still accessible from the selected car via links, so may be relevant.

Release screws (1).

Tightening torque: 11 65 4AZ .

Fig 1: Identifying Screws

Courtesy of BMW OF NORTH AMERICA, INC.

Raise vacuum unit (1) slightly.

Release chain tensioner (2).

Tightening torque 11 31 7AZ .

IMPORTANT: Have a cleaning cloth ready. A small quantity of engine oil will escape after the screw connection has been released.
Make sure no engine oil runs onto belt drive.

Installation note:

Replace sealing ring.

Fig 2: Identifying Vacuum Unit And Chain Tensioner

Courtesy of BMW OF NORTH AMERICA, INC.

If the chain tensioner is reused, its oil chamber must be drained.

Place chain tensioner on a level support and slowly compress.

Repeat process twice.

Fig 3: Draining Oil Chamber Of Chain Tensioner

Courtesy of BMW OF NORTH AMERICA, INC.

Assemble engine.

Installation note:

BLEEDING INSTRUCTION must be observed without fail.