Remove/install catalytic converter

AR49.20-P-0100MSA

Remove/install catalytic converter

23.07.2019

Engine

256.9 in model 213, 238, 257, 290

Modification notes

09.07.2019

Method description adapted

Operation steps 7, 8

Shown on engine 256.9 without code 494 (USA version)

1

Turbocharger

2

Catalytic converter

3

Heat shield

4

Electrical connectors

5

Bolts

6

Heat shield

7

Bolts

8

Heat shield

G3/1

Oxygen sensor downstream of catalytic converter

G3/2

Oxygen sensor upstream of catalytic converter

Shown on engine 256.9 with code 494 (USA version)

1

Turbocharger

2

Catalytic converter

3

Heat shield

4

Electrical connectors

5

Bolts

6

Heat shield

7

Bolts

8

Heat shield

9

Heat shield

G3/1

Oxygen sensor downstream of catalytic converter

G3/2

Oxygen sensor upstream of catalytic converter

 Warning

Risk of burn injuries, suffocation and poisoning when working on the exhaust system and the components connected to it. Risk of suffocation and risk of poisoning caused by inhalation of gaseous and solid components of the exhaust. Risk of poisoning caused by skin contact with solid components of the exhaust.

Wear protective clothing and safety glasses. Use the extraction system. Move people out of the hazard area.

AS49.00-Z-0001-01A

 Caution

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

Topical note

Notes on avoiding damage through contamination and foreign objects

AH00.00-P-5000-01A

Topical note

Notes on self-locking nuts and bolts

AH00.00-N-0001-01A

 

Remove/install

1

Remove upper engine cover.

AR01.10-P-2405MSA

 Installation: Only install upper engine cover after the leak test.

2

Remove heat shield (9).

Engine 256.9 in model 213, 238, 257, 290
with code 494 (US version)

 Nut, heat shield to exhaust gas turbocharger

*BA09.40-P-1004-02MRT

3

Remove heat shield (3).

 Nut, heat shield to exhaust gas turbocharger

*BA09.40-P-1004-02MRT

4

Release and disconnect electrical connectors (4) and unclip electric lines.

5

Remove exhaust system from catalytic converter (2).

AR49.10-P-7142MSA

 Installation: Only install center and rear lower rear engine compartment paneling again after leak test.

6

Remove bolts (5).

 Bolt, catalytic converter to bracket

*BA49.10-P-1005-02P

7

Remove bolts_(7).

 Bolt, catalytic converter to bracket

*BA49.10-P-1005-02P

8

Release upper screw of heat shield (8) and release heat shield (8) from clamp on heat shield (6).

 The heat shield (8) remains in vehicle.

 M61

*BA00.10-P-1002-04A

9

Remove clamp between exhaust gas turbocharger (1) and catalytic converter (2).

 Installation: Replace clamp.
Replace seal.

 Profile clamp, exhaust system to exhaust gas turbocharger

*BA09.40-P-1001-02MRT

10

Remove catalytic converter (2).

11

Remove oxygen sensor upstream of catalytic converter (G3/2).

When replacing catalytic converter (2).

AR07.04-P-0086MSA

12

Remove oxygen sensor downstream of catalytic converter (G3/1).

When installing new catalytic converter (2).

AR07.04-P-0085MSA



Clean

13

Remove combustion and corrosion residue at connecting points.

14

Install in the reverse order.

 Warning

Risk of accident from vehicle starting off by itself when engine running. Risk of injury (bruises and burns) resulting from working on the engine while it is being started or when it is running.

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

AS00.00-Z-0005-01A

15

Perform an engine test run; check the engine for proper operation and the exhaust system for leaks.

16

Install center and rear lower engine compartment lining.

Engine 256.9 in model 213, 238

AR61.20-P-1105LWE

Engine 256.9 in model 290

AR61.20-P-1105FRX

Engine 256.9 in model 257

AR61.20-P-1105FR

17

Install upper engine cover.

AR01.10-P-2405MSA

 Metric screws/bolts and nuts as per MBN 10 105, 10 143

Number

Designation

8.8

10.9

BA00.10-P-1002-04A

M61

Nm

9

13

 Turbocharger

Number

Designation

Engine 256.9

BA09.40-P-1001-02MRT

Profile clamp, exhaust system to exhaust gas turbocharger

Nm

17

 Turbocharger

Number

Designation

Engine 256.9

BA09.40-P-1004-02MRT

Nut, heat shield to exhaust gas turbocharger

Nm

8

 Exhaust system

Number

Designation

Model 213 with engine 256

Model 238 with engine 256

BA49.10-P-1005-02P

Bolt, catalytic converter to bracket

Nm

20

20

 Exhaust system

Number

Designation

Model 257 with engine 256

Model 290 with engine 256

BA49.10-P-1005-02P

Bolt, catalytic converter to bracket

Nm

20

20