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

Engine 177 in model 253

Courtesy of MERCEDES-BENZ USA

	Risk of injury to skin and eyes suffering scalding from contact with hot coolant spray. 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
	Notes on coolant		AH20.00-N-2080-01A
	Notes on coolant level		AH20.00-P-1142-01CW
	Remove
1	Remove engine compartment paneling		AR61.20-P-1105LW
2	Remove cap (1)	The coolant temperature should be approx. 40°C.
	Check
3	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
4	Attach tester cap (4) to low-temperature circuit expansion reservoir (2)	Test cap	Fig 1
5	Connect pressure pump (3) to tester cap (4)	Pressure pump	Fig 2
6	Apply compressed air to low-temperature circuit for 2 minutes at the test pressure	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
7	Perform a visual inspection on the assembly parts carrying coolant	In the event of pressure loss. Check condition and coolant loss for all assembly part carrying coolant and connections and remove coolant loss if necessary using suitable measures.
8	Actuate pressure relief button on pressure pump (3) and relieve the pressure	Pressure pump	Fig 2
9	Detach pressure pump (3) at tester cap (4)	Pressure pump	Fig 2
10	Remove tester cap (4) from low-temperature circuit expansion reservoir (2)	Test cap	Fig 1
11	Check coolant level and antifreeze content of coolant and correct if necessary	Cooling system	*BF20.00-P-1001-02LA
		Coolant mixing ratio	*BF20.00-P-1001-04A
	Install
12	Attach cap (1) to low-temperature circuit coolant expansion reservoir (2)
13	Install lower engine compartment paneling		AR61.20-P-1105LW

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 253
BF20.00-P-1001-02LA	Cooling system	Workshop replacement amount	Main circuit	Liter	≈11, 1
		Workshop replacement amount	Low-temperature circuit	Liter	≈4, 6
		Antifreeze/water	Down to -37°C	%	50/50
			-38°C and below	%	55/45
			Specifications for Operating Fluids, sheet		BB00.40-P-0310-01A
			Specifications for Operating Fluids, sheet		BB00.40-P-0325-06A
			Specifications for Operating Fluids, sheet		BB00.40-P-0326-06A

COOLANT MIXING RATIO

Number	Designation				Engine all (4xWD, CAR, smart)
BF20.00-P-1001-04A	Coolant mixing ratio	Antifreeze/water	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