18 12 031 Replacing rear silencer (N20)

Special tools required: 

• 31 2 220

Support rear silencer with special tool 31 2 220 and a suitable universal lifter and secure against falling out.

Fig 1: Supporting Exhaust System Using Special Tool (31 2 220)

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Necessary preliminary tasks: 

• F07, F11 only: 

  Remove left trailing link.

Carry over separation point to faulty rear silencer and mark.

Secure rear silencer against falling off.

Cut through exhaust pipe at marked point with a suitable tool.

Fig 2: Identifying Cutting Line Mark On Rear Silencer

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Unfasten nut.

Tightening torque 18 31 3AZ .

Fig 3: Identifying Rear Silencer (N20) Nut

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Spray bolt (1) and rubber mount with lubricant 5.2 .

Release screw (1).

Lower and remove exhaust system with assistance of a second person.

Installation note: 

Risk of damage to screw (1) and retaining plate thread.

Observe screwing sequence  .

1. Firstly apply nut to body at rear.
2. Then join bolt (1) exactly and secure. If necessary support rear silencer using a suitable jack.

   Tightening torque 18 31 6AZ .

   Fig 4: Identifying Join Bolt

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.

Detach pressure hose (1).

Slacken nut (2).

Tightening torque 18 31 5AZ .

Lower the rear silencer with the assistance of another person and remove it.

Fig 5: Identifying Pressure Hose And Nut

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Installation note: 

Connect front silencer to rear silencer by means of clamp and align.

Center clamp and tighten down.

Tightening torque 18 20 3AZ .

Fig 6: Identifying Front Silencer Center Clamps

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