Remove/Install Coolant Circuit Return Line Of Turbochargers - AR20.20-P-1101MNA

Engine 176 in model 463 

up to model year 2019 

Engine 177 in model 205 

Engine 178 in model 190 

Shown on model 205 with engine 177 

Courtesy of MERCEDES-BENZ USA

Shown on model 205 with engine 177 

Courtesy of MERCEDES-BENZ USA

Shown on model 205 with engine 177 

Courtesy of MERCEDES-BENZ USA

Shown on model 205 with engine 177 

Fig 1: Coolant Circuit Return Line Of Turbochargers Component Location - Model 205 W/ Engine 177

Courtesy of MERCEDES-BENZ USA

	Risk of injury  . Skin or eye injuries may result when handling hot or glowing objects.	Wear protective gloves, protective clothing and safety glasses, if necessary.	AS00.00-Z-0002-01A
	Risk of injury  to skin and eyes suffering scalding from contact with hot coolantspray. Risk of poisoning  from swallowing coolant.	Do not open cooling system unless coolant temperature is below 90°C. Open cap slowly and release the overpressure. Do not pour coolant into beverage containers. Wear protective gloves, protective clothing and safety glasses.	AS20.00-Z-0001-01A
	Risk of injury  . Skin or eye injuries may result when handling hot or glowing objects.	Wear protective gloves, protective clothing and safety glasses, if necessary.	AS00.00-Z-0002-01A
	Risk of injury  to skin and eyes due to handling of engine oil. Risk of poisoning  caused by swallowing engine oil	Wear protective gloves, protective clothing and safety glasses. Do not fill engine oil into beverage containers.	AS18.00-Z-0001-01A
	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
	Risk of injury  to skin and eyes due to handling of engine oil. Risk of poisoning  caused by swallowing engine oil	Wear protective gloves, protective clothing and safety glasses. Do not fill engine oil into beverage containers.	AS18.00-Z-0001-01A
Notice	Notes on coolant		AH20.00-P-2080-01KOA
Notice	Notes on avoiding damage through contamination and foreign objects		AH00.00-P-5000-01A
	Notes on coolant level		AH20.00-P-1142-01CW
	Remove/install
1	Drain off low-temperature circuit coolant.	Engine 178.9 in model 190.381	AR20.00-P-1144MNJ
		Engine 176 in model 463 up to model year 2019	AR09.41-P-6834MNF
		Engine 178 in model 190 (except 190.381)	AR09.41-P-6834MNB
		Engine 177 in model 205	AR09.41-P-6834MNA
2	Remove left and right air filter housing.	Engine 176 in model 463 up to model year 2019 Engine 177 in model 205
			AR09.10-P-1150MNA
3	Remove cover (31).	Engine 176 in model 463 up to model year 2019 Engine 177 in model 205 Engine 178 in model 190 (except 190.381) Check for correct seating of the cover (31).
4	Remove screws (2).	Bolt, rear heat shield to bracket	*BA09.40-P-1008-01ZA
		Bolt, upper heat shield to bracket/side heat shield	*BA09.40-P-1006-01ZA
5	Remove heat shield (1).
6.1	Unclip the electric lines (8, 14) on the heat shield (21).	Engine 177 in model 205
		Dismantling tool	Fig 3
6.2	Unclip electric lines (8) from heat shield (21).	Engine 178 in model 190 (except 190.381)
		Dismantling tool	Fig 3
6.3	Unclip electric lines (14) from heat shield (21).	Engine 176 in model 463 up to model year 2019
		Dismantling tool	Fig 3
7	Remove ignition coil (16).	Engine 178 in model 190	AR15.12-P-2008MNB
		Engine 176 in model 463 up to model year 2019 Engine 177 in model 205	AR15.12-P-2003MNA
8	Remove screw (32).	Engine 176 in model 463 up to model year 2019 Engine 177 in model 205 Engine 178 in model 190.381
9	Remove screws/bolts (22).	Bolt, side heat shield to cylinder head cover	*BA09.40-P-1007-01ZA
10	Remove heat shield (21).
11	Remove intake air duct downstream of left air filter housing.	Engine 178 in model 190
		Clamp, boot to exhaust gas turbocharger/air filter	*BA01.20-P-1003-01J
12	Remove boot at left exhaust gas turbocharger and place to one side.	Engine 178.9 in model 190.381	AR09.40-P-6026MNJ
		Engine 176 in model 463 up to model year 2019 Engine 177 in model 205 Engine 178 in model 190 (except 190.381)	AR09.40-P-6026MNA
13	Remove the brackets for the oil circuit feed line from the exhaust gas turbocharger.	Engine 176 in model 463 up to model year 2019 Engine 177 in model 205 Engine 178 in model 190 (except 190.381)
			AR09.40-P-6040MNA
14	Remove oil circuit feed line at left exhaust gas turbocharger and place to one side.	Engine 178.9 in model 190.381	AR09.40-P-6040MNJ
		Engine 176 in model 463 up to model year 2019 Engine 177 in model 205 Engine 178 in model 190 (except 190.381)	AR09.40-P-6040MNA
15	Remove screws (4).	Bolt, coolant line to turbocharger/cylinder head	*BA09.40-P-1004-01ZA
16	Remove screws (5).	Bolt, coolant line to turbocharger/cylinder head	*BA09.40-P-1004-01ZA
17	Remove screws (6).	Bolt, coolant line to turbocharger/cylinder head	*BA09.40-P-1004-01ZA
18	Remove screws (9).	Bolt, coolant line to turbocharger/cylinder head	*BA09.40-P-1004-01ZA
19	Remove screws_(7).	Bolt, coolant line to turbocharger/cylinder head	*BA09.40-P-1004-01ZA
20	Remove the coolant circuit return line (10) with the coolant circuit bleed line (3) by moving it upward.	Replace seals.
		Assembly tool	Fig 2
21	Remove coolant circuit bleed line (3) from coolant circuit return line (10).	When replacing the coolant circuit return line (10).
22	Install in the reverse order.
	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 danger zone.	AS49.00-Z-0001-01A
	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
23	Perform engine test run. While doing so, check engine for proper operation and leak tightness

Fig 2: Identifying Assembly Tool (000 589 93 63 00)

Courtesy of MERCEDES-BENZ USA

Fig 3: Identifying Dismantling Tool (000 589 95 63 00)

Courtesy of MERCEDES-BENZ USA