Remove/install catalytic converter

AR49.10-P-5500RTN

Remove/install catalytic converter

11.3.10

 

Remove/install

Danger!

Risk of death caused by vehicle slipping or toppling off the lifting platform.

Align vehicle between columns of vehicle lift and position four support plates at vehicle lift support points specified by vehicle manufacturer.

AS00.00-Z-0010-01A

 Danger!

Risk of injury to skin and eyes caused by handling hot or glowing objects.

Wear safety gloves, protective clothing and safety glasses, if necessary.

AS00.00-Z-0002-01A

Danger!

Risk of injury caused by scraping or cutting body parts on sharp vehicle parts

Always wear protective gloves when working on or near sharp and non-deburred vehicle parts.

Deburr repair panels.

AS00.00-Z-0017-01A



Notes on self-locking nuts and bolts

AH00.00-N-0001-01A



When working on exhaust system, connecting points have to be cleaned from combustion and corrosion residues before the installation of parts.

1

Detach lower engine compartment paneling (2)

AR61.20-P-1105RT

2

Unscrew two plastic nuts (arrows A) from underfloor paneling (3)

 Pull down underfloor paneling and do not damage it.

3

Remove bolts (4, 6) and remove left stiffening bridge (5)

 Installation: Pay attention to installation position of left stiffening bridge.

Engine 113

AR22.10-P-1170RT

Engine 156

AR22.10-P-1170GZS

4

Release clamp (7)

 Slide released hose clamp towards rear on center muffler. Replace defective or corroded hose clamp.



*BA49.10-P-1018-01X

5

Remove bolts (8, 9) and detach bracket (10)

 Installation: Attach shim plate between holder and transmission if not present.

Replace bolts (9).



*BA49.10-P-1001-01X



*BA49.10-P-1020-01X

6

Loosen heat shield (11) and pull towards rear

 Do not damage heat shield.

7

Expose and detach connector for left O2 sensor downstream of TWC (G3/5x1)

8

Expose and detach connector for left O2 sensor upstream of TWC (G3/3x1)

Only engine 156

 On engine 156, the position of connector for left O2 sensor upstream of TWC (G3/3x1) is below the transmission.

9

Unclip electrical line of left O2 sensor upstream of TWC (G3/3) and electrical line of left O2 sensor downstream of TWC (G3/5)

Only Motor 156

10

Detach left catalytic converter (1) from left exhaust manifold

 Secure left catalytic converter against falling down.



*BA49.10-P-1002-01X

11

Expose and detach connector for left O2 sensor upstream of TWC (G3/3x1)

Only engine 113

 On engine 113.971, position of left O2 sensor upstream of TWC connector (G3/3x1) is in the left front above transmission.

12

Remove left catalytic converter (1)

 Do not damage surrounding components.



Notes on disposing of catalytic converters

OS49.10-P-1000-01A

13

Detach left O2 sensor upstream of TWC (G3/3) and left O2 sensor downstream of TWC (G3/5) from left catalytic converter (1)

Only when replacing the left catalytic convertor.

 Installation: Apply heat-resistant lubricant to thread of left O2 sensor upstream of TWC (G3/3) and left O2 sensor downstream of TWC (G3/5).



*BA14.00-P-1002-01A

Paste

*BR00.45-Z-1005-06A

14

Install in the reverse order



Checking

15

Check installation position and for unobstructed movement of entire exhaust system

 The exhaust system must be mounted free of tension, align exhaust system if required.

 Danger!

Risk of accident caused by vehicle starting off by itself when engine is running. Risk of injury caused by contusions and burns during starting procedure or when working near the engine as it is running

Secure vehicle to prevent it from moving by itself.
Wear closed and snug-fitting work clothes.
Do not touch hot or rotating parts.

AS00.00-Z-0005-01A

16

Conduct an engine test run and inspect exhaust system for leaks

Number

Designation

Engine
113.971

Engine
156

BA14.00-P-1002-01A

O2 sensor to catalytic converter

Nm

50

50

Number

Designation

Engine 113 in model 251

Engine
156 in model 251

BA49.10-P-1001-01X

Bolt, catalytic converter bracket to catalytic convertor

Nm

20

20

BA49.10-P-1002-01X

Bolt, flange connection to exhaust pipe/exhaust manifold

Nm

20

20

BA49.10-P-1018-01X

Bolt, rear muffler hose clamp to catalytic converter

Nm

35

35

BA49.10-P-1020-01X

Bolt, catalytic converter bracket to transmission

Stage 1

Nm

8

8

Stage 2

°

60

60

Number

Designation

Order number

BR00.45-Z-1005-06A

Paste, hot lubrication 1 kg, DB supply specification 6879.20

A 000 989 76 51