Remove/install coolant thermostat - AR20.10-P-2460GZS (ML63 AMG)

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ENGINE 156 in MODEL 164, 251

Fig 1: Identifying Coolant Thermostat Components

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

	Remove/install
	Risk of injury to skin and eyes caused by scalding from contact with hot coolant spray. Risk of poisoning caused by 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
	Risk of death caused by vehicle slipping or toppling off the lifting platform.	Align vehicle between columns of lifting platform and position four support plates at lifting platform support points specified by vehicle manufacturer.	AS00.00-Z-0010-01A
	Risk of injury caused by fingers being pinched or crushed when removing, installing or aligning hoods, doors, trunk lids, tailgates or sliding roof.	Keep body parts and limbs well clear of moving parts.	AS00.00-Z-0011-01A
	Notes on coolant	All engines	AH20.00-N-2080-01A
	Notes on avoiding damage to electronic components due to electrostatic discharge	All models	AH54.00-P-0001-01A
1	Turn key in ignition switch to position "0".	On vehicles with code 889, Keyless Go: Press keyless go start/stop button repeatedly until ignition is switched off
2	Open engine hood	Model 164	AR88.40-P-1000GZ
		Model 251	AR88.40-P-1000RT
3	Remove front engine cover	Do not tilt front engine cover, but lift upwards vertically otherwise retaining lugs can break off.
4	Remove the right and left intake air duct
5	Remove switchover valve		AR14.30-P-7255GZS
6	Loosen expansion reservoir for steering and place to one side		AR46.25-P-1000GZS
7	Raise vehicle with lifting platform	Model 164	AR00.60-P-1000GZ
		Model 251	AR00.60-P-1000RT
8	Remove lower engine compartment paneling	Model 164	AR61.20-P-1105GZ
		Model 251	AR61.20-P-1105RT
9	Drain coolant from radiator		AR20.00-P-1142GZS
10	Detach upper coolant hose (1) from coolant thermostat housing (2) and place it to one side	Installation: Install new O-ring.
11	Remove overflow line from coolant thermostat housing (2) to coolant expansion reservoir and set aside
12	Unlatch electrical connector at three-disk thermostat valve (Y110) and disconnect	Also disconnect connector on underside of thermostat housing.
13	Remove bolts (2a)		*BA20.10-P-1002-01V
14	Pull out coolant thermostat housing (2) with coolant thermostat from timing case cover	The coolant thermostat and coolant thermostat housing (2) are a single unit. The coolant thermostat must not be taken out of coolant thermostat housing (2) as it can get damaged in the process. Installation: Install new O-ring and seal.
15	Install in the reverse order
16	Inspect cooling system for leaks		AR20.00-P-1010GZS
	Checking
	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
17	Carry out engine test run

COOLANT PUMP, COOLANT THERMOSTAT

Number	Designation			Engine 156
BA20.10-P-1002-01V	Bolt, thermostat on timing case cover	M6x25	Nm	8.5
BA20.10-P-1002-01V	Bolt, thermostat on timing case cover	M8x80	Nm	20