18 12 045 Replacing center silencer (B36, B38)

WARNING:

Danger of burning and other injuries!

This repair work may only be carried out on an exhaust system which has cooled down.

Removal of the center silencer must be carried out with the assistance of a second person.

Necessary preliminary tasks:

Use a suitable jack to support and secure the center silencer against falling.

Fig 1: Locating Cover Screws

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Removal:

Loosen screws.

Remove cover (1).

Fig 2: Rear Silencer Rubber Mount

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NOTE: If the separation point is not marked by a punch mark in the pipe, determine the separation point by means of the pipe length on the new center silencer.
Carry over separation point to faulty center silencer and mark.
Secure center silencer against falling off.
Cut through exhaust pipes at marked point with a suitable tool.

Fig 3: Connection Carrier Screws

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F56 only:

Loosen screws (1).

Remove connection carrier.

Fig 4: Connection Carrier Screws

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F55 only:

Loosen screws (1).

Remove front connection carrier (2).

Loosen screws (3).

Remove rear connection carrier (4).

Fig 5: Front Or Rear Connection Carrier And Screws

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Release clamp (1).

Replace clamp (1).

Parts: Clamp.

Lower and remove center silencer with assistance of a second person.

Fig 6: Exhaust System Clamp (Version 1: Ribbon Clamp)

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Installation:

Install new center silencer.

Tighten clamp (1).

Tightening torque 18 20 1AZ .

Fig 7: Clamp

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Adjust new center silencer and connect by clamp to rear silencer.

Center clamp and tighten down.

Tightening torque 18 20 3AZ .

Fig 8: Rear Silencer Clamp

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F56 only:

Install connection carrier.

Tighten down screws (1).

Tightening torque 18 30 4AZ .

Fig 9: Connection Carrier Screws

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F55 only:

Install front connection carrier (2).

Tighten down screws (1).

Tightening torque 18 30 7AZ .

Install rear connection carrier (4).

Tighten down screws (3).

Tightening torque 18 30 4AZ .

Fig 10: Connection Carriers And Screws

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Position cover (1).

Tighten the screws.

Fig 11: Locating Cover Screws

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Required follow-up work:

Check exhaust system for leak tightness.