18 12 050 Replacing center muffler (N55)

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Special tools required:

31 2 220

WARNING: Scalding hazard!
Only perform these tasks after exhaust system has cooled down.

Support center silencer with special tool 31 2 220 and a suitable universal lifter.

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

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Release screws (1).

Remove heat shield (2).

Fig 2: Identifying Heat Shield With Screws

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Release screws (1).

Tightening torque 18 31 4AZ .

Only when independent heating is fitted: release screw (2) on metering pump.

Tightening torque 18 31 5AZ .

Release screws (3) on underbody panels.

Remove reinforcement plate (4).

Fig 3: Identifying Reinforcement Plate And Screws

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

Fig 4: Identifying Cutting Points On Pipes

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Picture shows the left side, the procedure for the right side is identical.

Slacken nut (1).

Tightening torque 18 20 3AZ .

Fig 5: Identifying Nut

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Installation:

Adjust center muffler to fit and connect with clamps.

Center clamp and tighten down.

Tightening torque 18 31 7AZ .

The procedure is identical on both sides.

Fig 6: Identifying Center Muffler And Clamps

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NOTE: Check exhaust system for leaks.