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

Engine 176 In Model 167

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
Notice	Notes on coolant		AH20.00-P-2080-01KOA
	Notes on coolant level		AH20.00-P-1142-01CW
	Remove
1	Remove upper engine cover.		AP01.10-P-2405-01M

2	Remove lower engine compartment paneling.		AR61.20-P-1105ME
3	Remove cap at expansion reservoir (1).
	Check
4	Check coolant level and antifreeze content of coolant in low-temperature circuit and correct if necessary	Coolant mixing ratio	*BF20.00-P-1001-04A
5	Attach tester cap (2) to low-temperature circuit expansion reservoir (1).	Test cap	Fig 1
6	Connect pressure pump (3) to tester cap (2).	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	Perform visual check of coolant-carrying components.	If a pressure loss is determined. Check condition of and for coolant loss at all coolant-carrying components and connections and eliminate coolant loss via suitable measure if necessary.
9	Actuate pressure release button on pressure pump (3) and reduce pressure.	Pressure pump	Fig 2
10	Disconnect pressure pump (3) from tester cap (2).	Pressure pump	Fig 2
11	Remove tester cap (2) from low-temperature circuit expansion reservoir (1).	Test cap	Fig 1
12	Check coolant level and antifreeze content of the coolant and correct if necessary.	Coolant mixing ratio	*BF20.00-P-1001-04A
	Install
13	Attach cap to low-temperature circuit expansion reservoir (1).
14	Install lower engine compartment lining.		AR61.20-P-1105ME
15	Install upper engine compartment cover.
			AP01.10-P-2405-01M

COOLING SYSTEM CHECK VALUES

Number	Designation		Engine 176
BE20.30-P-1001-01D	Test pressure for pressure-testing the Overpressure low-temperature circuit	bar	1, 4

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 specification sheet		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