1812050 Replacing center muffler (N63): Notes

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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: Identifying Centre Silencer With Special Tool 31 2 220

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Release screws (1).

Tightening torque 18 20 6AZ .

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

Tightening torque 18 20 7AZ .

Release screws (3) on underbody panels.

Remove reinforcement plate (4).

Fig 2: Identifying Screw On Metering Pump, Screws On Underbody Panels And Reinforcement Plate

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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 3: Identifying Cutting Line On Centre Muffler

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

Slacken nut (1).

Tightening torque 18 20 4AZ .

Fig 4: Identifying Exhaust System Nut

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Installation:

Adjust center muffler to fit and connect with clamps.

Centre clamp and tighten down.

Tightening torque 18 31 4AZ .

The procedure is identical on both sides.

Fig 5: Identifying Centre Muffler With Clamps

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NOTE: Check exhaust system for leaks.