18 32 050 Removing and installing/replacing catalytic converter cylinders 5-8 (S63)

Necessary preliminary tasks: 

• Remove top HEAT SHIELD .
• Remove EXHAUST SYSTEM .

Release screws (1).

Tightening torque 18 32 3AZ .

Release screw (2).

Tightening torque 18 32 2AZ .

Remove bracket (3).

Fig 1: Identifying Bracket And Screws

Courtesy of BMW OF NORTH AMERICA, INC.

Unscrew nuts (1).

Tightening torque 18 32 4AZ .

Unfasten screws (2).

Tightening torque 18 32 3AZ .

Remove bracket (3).

Fig 2: Identifying Bracket, Screws, And Nuts

Courtesy of BMW OF NORTH AMERICA, INC.

Release screw (1).

Tightening torque 18 32 1AZ .

Remove and renew clamp (2).

Remove catalytic converter cylinders 5-8 towards top.

Installation note: 

Clamps must be installed with the screws toward the inside (Figure). Otherwise, a top heat shield can no longer be installed.

Fig 3: Identifying Clamps And Screws

Courtesy of BMW OF NORTH AMERICA, INC.

Installation note: 

The ends of the V-band clamps must rest parallel to each other.

Tightening torque 18 32 1AZ .

Fig 4: Identifying V-Band Clamp Ends

Courtesy of BMW OF NORTH AMERICA, INC.

Installation note: 

If you can see a gap between the ends of the V-band clamps, release and then repeat the screw connection.

Tightening torque 18 32 1AZ .

Fig 5: Identifying Gap Between Ends Of V-Band Clamps

Courtesy of BMW OF NORTH AMERICA, INC.

Installation note: 

If the ends of the V-band clamps are positioned under each other, release and then repeat the screw connection.

Tightening torque 18 32 1AZ .

Fig 6: Identifying Misalignment Of V-Band Clamp Ends

Courtesy of BMW OF NORTH AMERICA, INC.

Assemble engine.

Check exhaust system for leaks.