18 32 050 Removing and installing/renewing catalytic converters for cylinders 1-4 (S63)

Necessary preliminary tasks: 

• Remove upper HEAT SHIELD .
• Remove EXHAUST SYSTEM .

Release screw (1).

Tightening torque 18 32 2AZ .

Unfasten screws (2).

Tightening torque 18 32 3AZ .

Remove bracket (3).

Unscrew nuts (4).

Tightening torque 18 32 4AZ .

Release screws (5).

Tightening torque 18 32 3AZ .

Remove holder (6).

Fig 1: Identifying Holder, Bracket, Nuts, And Screws

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Release screw (3).

Tightening torque 18 32 1AZ .

Remove and replace clamp (4).

Remove catalytic converters for cylinders 1-4 upward.

Installation note: 

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

Fig 2: Identifying Clamps And Screws

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Installation note: 

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

Tightening torque 18 32 1AZ .

Fig 3: Identifying V-Band Clamp Ends

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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 4: Identifying Gap Between Ends Of V-Band Clamps

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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 5: Identifying Misalignment Of V-Band Clamp Ends

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Assemble engine.

Check exhaust system for leaks.