LEMON Manuals: Even more car manuals for everyone
Home >> Mercedes Benz >> 2019 >> CLS450 Base >> Repair and Diagnosis >> Engine Mechanical >> Blowers, Superchargers & Turbochargers >> Engine Cooling System - 257 Chassis >> Testing & Repair >> Remove/Install Coolant Thermostat - AR20.10-P-2461MSA

Remove/Install Coolant Thermostat - AR20.10-P-2461MSA

Engine 256.9 in model 213, 238, 257, 290 

MODIFICATION NOTES

13.07.2020 Insertion of an operation step variant for the removal/installation of the catalytic converter/exhaust gas aftertreatment unit Operation step 3.1/3.2  
13.07.2020 DIN baseline date replaced with BA22.10-P-1003-02A, BA22.10-P-1005-02A and BA22.10-P-1004-02A Operation step 4  
Fig 1: Coolant Thermostat Component Location - Engine 256.9 model 257
G14548326Courtesy of MERCEDES-BENZ USA
WARNING 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 pressure. Do not pour coolant into beverage containers.
Wear protective gloves, protective clothing and safety glasses.
AS20.00-Z-0001-01A 
WARNING 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
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 Information on preventing damage to electronic components due to electrostatic discharge   AH54.00-P-0001-01A
Topical note Notes on avoiding damage through contamination and foreign objects   AH00.00-P-5000-01A
REMOVINGINSTALLING Remove/install     
1 Remove upper engine cover.   AR01.10-P-2405MSA
2 Drain off coolant.   AR20.00-P-1142MSA 
3.1 Remove the catalytic converter. Engine 256.9 in model 213, 238 up to model year 2020 with code 494 (US version)
Engine 256.9 in model 257, 290 with code 494 (US version)
 
      AR49.20-P-0100MSA
3.2 Remove exhaust gas aftertreatment unit. Engine 256.9 in model 213, 238 as of model year 2020
with code 494 (US version)
 
      AR49.20-P-1500MSA
4 Remove the front and center heat shield unde the catalytic converter. Engine 256.9 in model 213, 238, 257, 290 except code 494 (US version)  
    TORQUE SPECIFICATION Bolt, heat shield to engine support *BA22.10-P-1003-02A 
    TORQUE SPECIFICATION Bolt, heat shield to timing case *BA22.10-P-1005-02A 
    TORQUE SPECIFICATION Screw, heat shield to crankcase/catalytic converter bracket/engine mount heat shield *BA22.10-P-1004-02A 
5 Disconnect the coolant hose (14) from the connecting pipe and seal the openings using suitable protective covers.   AR20.20-P-7441-01RQ 
    SPECIAL TOOL Set of protective covers Fig 2
6 Unscrew the screw (18). TORQUE SPECIFICATION Screw, coolant connecting pipe to cylinder head *BA20.20-P-1002-02MR 
7 Unclip the electrical line on the connecting pipe for the coolant thermostat (12).    
8 Remove the bracket of the oxygen sensor connector from the cylinder head. TORQUE SPECIFICATION Screw, electrical connector bracket to cylinder head *BA15.18-P-1004-01MR 
9 Remove the coolant hoses (2, 3) from the coolant thermostat (12) and seal the openings using suitable protective covers. SPECIAL TOOL Set of protective covers Fig 2
10 Release and disconnect the electrical connection (17) on the coolant thermostat (12).    
11 Unscrew the screws (13) in reverse order of the tightening procedure and remove the coolant thermostat (12). Coolant thermostat tightening procedure AR20.10-P-2461-01MRT 
    INSTALLATION IMPORTANT Replace seals.  
    TORQUE SPECIFICATION Screw/bolt, coolant thermostat to crankcase *BA20.10-P-1001-01MR 
CLEAN Clean     
12 Clean sealing surfaces on the coolant thermostat (12) and crankcase. IMPORTANT Use lint-free rags.  
13 Install in the reverse order.    
12 V ON-BOARD ELECTRICAL SYSTEM ENGINE WIRING HARNESS

Number Designation Engine 256
BA15.18-P-1004-01MRT Screw, electrical connector bracket to cylinder head Nm 8
COOLANT THERMOSTAT, COOLANT PUMP

Number Designation Engine 256
BA20.10-P-1001-01MRT Screw/bolt, coolant thermostat to crankcase Nm 8
ENGINE RADIATOR, COOLANT HOSES AND LINES

Number Designation Engine 256
BA20.20-P-1002-02MRT Screw, coolant connecting pipe to cylinder head Nm 8
ENGINE SUPPORT (ENGINE SIDE)

Number Designation Engine 256
BA22.10-P-1003-02A Bolt, heat shield to engine support Nm 12
ENGINE SUPPORT (ENGINE SIDE)

Number Designation Engine 256
BA22.10-P-1004-02A Screw, heat shield to crankcase/catalytic converter bracket/engine mount heat shield Nm 8
ENGINE SUPPORT (ENGINE SIDE)

Number Designation Engine 256
BA22.10-P-1005-02A Bolt, heat shield to timing case Nm 8
Fig 2: Identifying Set Of Protective Covers (001 589 01 91 00)
G07742161Courtesy of MERCEDES-BENZ USA