Check Low-Temperature Circuit For Leaktightness - AR09.41-P-1011MNI

Engine 177 in model 290 

Courtesy of MERCEDES-BENZ USA

	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
Notice	Notes on coolant		AH20.00-P-2080-01KOA
	Notes on coolant level		AH20.00-P-1142-01CW
	Remove
1	Remove lower engine compartment paneling.		AR61.20-P-1105FRX
2	Remove upper engine cover.
3	Remove cap (1).	The coolant temperature should be approx. 40°C.
	Check
4	Check coolant level and antifreeze content of coolant in low-temperature circuit and correct if necessary	Cooling system	*BF20.00-P-1001-02LA
		Coolant mixing ratio	*BF20.00-P-1001-04A
5	Attach the tester cap (3) to the low-temperature circuit expansion reservoir (2).	Test cap	Fig 1
6	Connect pressure pump (4) at tester cap (3).	Pressure pump	Fig 2
7	Apply compressed air to the low-temperature circuit for 2 minutes.	Do not exceed the specified test pressure. Otherwise the low-temperature circuit will be damaged.
		There should be no pressure loss within a period of 2 minutes.
		Test pressure for pressure-testing the low-temperature circuit	*BE20.30-P-1001-01D
8	Check all coolant-conducting component parts and connections of low-temperature circuit for condition and coolant loss, and replace if necessary.	In the event of pressure loss.
9	Actuate pressure relief button on pressure pump (4) and relieve pressure.	Pressure pump	Fig 2
10	Disconnect pressure pump (4) from tester cap (3).	Pressure pump	Fig 2
11	Remove the tester cap (3) from the low-temperature circuit expansion reservoir (2).	Test cap	Fig 1
12	Check coolant level and antifreeze content of the coolant and correct if necessary.	Cooling system	*BF20.00-P-1001-02LA
		Coolant mixing ratio	*BF20.00-P-1001-04A
	Install
13	Attach cap (1) to the low-temperature circuit expansion reservoir (2).
14	Install upper engine cover.
15	Install lower engine compartment lining.		AR61.20-P-1105FRX

COOLING SYSTEM CHECK VALUES

Number	Designation			Engine 177
BE20.30-P-1001-01D	Test pressure for pressure-testing the low-temperature circuit	Overpressure	bar	1, 4

COOLING SYSTEM

Number	Designation				Engine 177 in model 290 except code ME10 (Hybrid vehicle (plug-in, PHEV))	Engine 177 in model 290 with code ME10 (Hybrid vehicle (plug-in, PHEV))
BF20.00-P-1001-02LA	Cooling system	Workshop replacement amount	Main circuit	Liter	≈15, 3	≈14, 3
			Low Temp. circuit 1	Liter	≈6, 4	≈10, 7
			Low Temp. circuit 2	Liter	-	≈5, 6
		Antifreeze/water	Down to -37°C	%	50/50	50/50
			-38°C and below	%	55/45	55/45
			Operating Fluids, Specifications		BB00.40-P-0310-01A	BB00.40-P-0310-01A
			Operating Fluids, Specifications		BB00.40-P-0325-06A	BB00.40-P-0325-06A
			Operating Fluids, Specifications		BB00.40-P-0326-06A	BB00.40-P-0326-06A

COOLANT MIXING RATIO

Number	Designation				All engines, except engine 178 in model 190.381
BF20.00-P-1001-04A	Coolant mixing ratio	Antifreeze/water	Up to -25°C	%	-
			Up to -37°C	%	50/50
			As of -38°C	%	55/45
			Overview and specifications sheet		BB00.40-P-0310-01A
			References to sheet specification		BB00.40-P-0310ZZ

Fig 1: Identifying Test Cap (210 589 00 91 00)

Courtesy of MERCEDES-BENZ USA

Fig 2: Identifying Pressure Pump (124 589 24 21 00)

Courtesy of MERCEDES-BENZ USA