Remove/install exhaust aftertreatment unit

AR49.20-P-1500MSA

Remove/install exhaust aftertreatment unit

26.05.2020

Engine

256.9 in model 213, 238

as of model year 2020

1

Exhaust aftertreatment unit

6

Heat shield

2

Heat shield

7

Bolts

3

Heat shield

8

Bolts

4

Electrical connectors

G3/1

Oxygen sensor downstream of catalytic converter

5

Heat shield

G3/2

Oxygen sensor upstream of catalytic converter

1

Exhaust aftertreatment unit

9

Clip

10

Pressure hoses

 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 (3).

 Nut/screw, heat shield to exhaust gas turbocharger/heat shield

*BA09.40-P-1004-02MRT

3

Remove heat shield (2).

 Nut/screw, heat shield to exhaust gas turbocharger/heat shield

*BA09.40-P-1004-02MRT

4

Remove pressure hoses (10) from exhaust gas aftertreatment unit (1) and seal openings with suitable stop plugs.

 Installation: Replace clamps.

 Pliers for click clamps

*171589003700

 Record plug

*129589009100

5

Release and disconnect the electrical connections (4).

6

Remove electric line of lambda sensor upstream of catalytic converter (G3/2) from engine.

AR07.04-P-0086MSA

7

Remove electric line of lambda sensor downstream of catalytic converter (G3/1) from engine.

AR07.04-P-0085MSA

8

Remove electric line of temperature sensor upstream of gasoline particulate filter (B163/4) from engine.

AR49.20-P-0200MSA

9

Remove exhaust system from exhaust gas aftertreatment unit (1).

AR49.10-P-7142MSA

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

10

Remove screws_(7).

 Bolt, catalytic converter to bracket

*BA49.10-P-1005-02P

11

Remove screws (8).

 Bolt, catalytic converter to bracket

*BA49.10-P-1005-02P

12

Release upper screw of heat shield (5) and release heat shield (5) from clip at heat shield (6).

 Heat shield (5) remains in vehicle.

 M61

*BA00.10-P-1002-04A

13

Remove clamp (9) between exhaust gas turbocharger and exhaust gas aftertreatment unit (1).

 Installation: Replace clamp and seal.

 Profile clamp, exhaust system to exhaust gas turbocharger

*BA09.40-P-1001-02MRT

14

Remove exhaust gas aftertreatment unit(1).

15

Remove combustion and corrosion residue at connecting points.

Assembly cleaner

*BR00.45-Z-1028-04A

16

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

17

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

18

Install center and rear lower engine compartment lining.

AR61.20-P-1105LWE

19

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/screw, heat shield to exhaust gas turbocharger/heat shield

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

Repair materials

Number

Designation

Order number

BR00.45-Z-1028-04A

Assembly cleaner

A 000 986 56 01