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

Unfasten cylinder for chain tensioning piston.

Fig 1: Identifying Cylinder For Chain Tensioning Piston

Courtesy of BMW OF NORTH AMERICA, INC.

Installation: 

Replace sealing ring.

Tightening torque, refer to 11 31 8AZ in ENGINE - TIGHTENING TORQUES .

Arrangement of components:

1. Cylinder for chain tensioning piston
2. Sealing ring
3. Spring
4. Piston
   Fig 2: Identifying Sealing Ring And Spring

   Courtesy of BMW OF NORTH AMERICA, INC.