18 32 050 Removing and installing/renewing catalytic converter cylinder 5-8 (N63)

WARNING: This page is about a different car, the 2013 BMW X5, 2012 BMW X5, and 2011 BMW X5. However, it is still accessible from the selected car via links, so may be relevant.

WARNING: Risk of burning!
Only perform this repair work on an engine that has cooled down.

Necessary preliminary tasks:

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

Release nuts (1) on left and right.

Tightening torque: 18 31 1AZ .

Lower exhaust system at front.

Replace self-locking nuts.

Replace gaskets.

Fig 1: Identifying Nuts Of Catalytic Converter Cylinder

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Release screws (1).

Tightening torque: 18 20 2AZ .

Fig 2: Identifying Screws

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Release screws (1).

Tightening torque: 18 20 1AZ .

Lower exhaust system slightly towards the front.

Fig 3: Identifying Screws Of Exhaust System

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Release screws (1).

Remove left cable clip (2).

Fig 4: Identifying Cable Clip And Screws

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Release screw (1) on catalytic converter.

Tightening torque: 18 32 4AZ .

Release clamp (2) on catalytic converter.

Replace clamp (2).

Tightening torque: 18 32 1AZ .

Installation note:

The clamp (2) must be installed with the screw toward the inside (illustration).

Otherwise, the heat shield can no longer be installed on top.

Fig 5: Identifying Clamp And Screw On Catalytic Converter

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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 6: Identifying V-Band Clamps

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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 7: Locating Gap 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 8: Locating Screw Connection Of V-Band Clamps

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Release screw (1) from heat shields (2) and (3).

Screw (1) is located between the catalytic converters.

Fig 9: Identifying Heat Shields And Screw

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NOTE: Picture shows the engine removed.

Release screws (1) on left heat shield.

Unclip left heat shield and remove.

Fig 10: Releasing Screws On Heat Shield

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NOTE: Picture shows the engine removed.

Release screw (1) on right heat shield.

Fig 11: Identifying Screw On Heat Shield

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NOTE: Picture shows the engine removed.

Release screw (1) on heat shield at bottom right.

Unclip heat shield and remove.

Fig 12: Releasing Screw On Heat Shield

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Release screws (1).

Detach hose (2) from cylinder head cover.

Release screws (3) on holder.

Tightening torque: 18 32 2AZ .

Fig 13: Identifying Hose And Screws On Holder

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NOTE: Picture shows the engine removed.

Release screws (1) on catalytic converter, cylinders 5-8, rear, at cylinder head.

Tightening torque: 18 32 3AZ .

Remove catalytic converter for cylinders 5-8.

Fig 14: Identifying Screws On Catalytic Converter

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Installation note:

Picture shows the engine removed.

Replace gasket (1) on left exhaust turbocharger.

Fig 15: Identifying Gasket On Left Exhaust Turbocharger

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Installation note:

Clean sealing surfaces.

Replace gasket (1).

Fig 16: Identifying Gasket

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Assemble engine.

Check exhaust system for leaks.