11 31 090 Removing and installing/replacing chain tensioning piston (M52 / M52TU / M54 / M56)

Unfasten cylinder for chain tensioning piston.

Installation: 

Replace sealing ring.

Tightening torque. Refer to ENGINE - TIGHTENING TORQUES - 3-SERIES (E46) .

Fig 1: Replacing Sealing Ring

Courtesy of BMW OF NORTH AMERICA, INC.

Arrangement of components:

1. Cylinder for chain tensioning piston
2. Sealing ring
3. Spring
4. Piston
   Fig 2: Identifying Arrangement Of Components

   Courtesy of BMW OF NORTH AMERICA, INC.