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

Engine 279 in model 223

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 engine cover.		AR01.10-P-2405SVZ
2	Carefully open cap (1.1) of low-temperature circuit expansion reservoir (1), release overpressure, and remove cap (1.1).
3	Check coolant level of low-temperature circuit, correct if necessary.	Cooling system	*BF20.00-P-1001-02GA
4	Attach tester cap (2) to low-temperature circuit expansion reservoir (1).	Test cap	Fig 1
5	Connect pressure pump (3) to tester cap (2).	Test cap	Fig 1
		Pressure pump	Fig 2
	Check
6	Apply test pressure to low-temperature circuit for 2 min.	Do not exceed the specified test pressure. Low-temperature circuit will otherwise be damaged. There should be no pressure loss within a period of 2 minutes. Test pressure for pressure-testing the engine cooling system	*BE20.30-P-1005-01A
7	Perform visual check of coolant-carrying component parts and connecting points for condition and coolant loss.	Where pressure loss is detected.
	Install
8	Release overpressure via valve on pressure pump (3).
9	Remove pressure pump (3) from tester cap (2).
10	Remove tester cap (2) from low-temperature circuit expansion reservoir (1).
11	Check coolant level and antifreeze content of low-temperature circuit, correct if necessary.	Cooling system	*BF20.00-P-1001-02GA
12	Seal low-temperature circuit expansion reservoir (1) with cap (1.1).
13	Install engine cover.		AR01.10-P-2405SVZ

RADIATOR OR EXPANSION RESERVOIR CAP

Number	Designation			1-stage cover latch	2-stage latch cover
BE20.30-P-1005-01A	Test pressure for pressure-testing the engine cooling system	Overpressure	bar	1, 4	1, 4

COOLING SYSTEM

Number	Designation				Engine 279 in model 223
BF20.00-P-1001-02GA	Cooling system	Workshop replacement amount	Main circuit	Liter	≈16, 0
		Workshop replacement amount	Low-temperature circuit	Liter	≈5, 0
		Antifreeze/water	Down to -37°C	%	50/50
			-38°C and below	%	55/45
			Specifications		BB00.40-P-0310-01A
			Specifications		BB00.40-P-0325-06A
			Specifications		BB00.40-P-0326-06A

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