Check low-temperature circuit cooling system for leaks - AR09.41-P-1010LW

MODEL 205 with ENGINE 274.9, 276.8, 651 

Shown: engine 651 in model 205 except code ME04 (HD 20 kW variant) 

Fig 1: Checking Low-Temperature Circuit Cooling System For Leaks - Shown On Model 205

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 pressure. Do not pour coolant into beverage containers. Wear protective gloves, protective clothing and safety glasses.	AS20.00-Z-0001-01A
	Risk of injury  caused by fingers being jammed or pinched when removing, installing or aligning hoods, doors, trunk lid/rear-end door or sliding roof.	No parts of the body or limbs should be within the operating area when the components are moving.	AS00.00-Z-0011-01A
	Notes on coolant		AH20.00-N-2080-01A
	Remove
1	Switch on ignition
2	Remove upper engine cover
3	Unscrew cap (1) on low-temperature circuit coolant expansion reservoir (2)
	Check
4	Check coolant level and antifreeze content coolant in low-temperature circuit	Coolant mixing ratio In a case of the antifreeze content of the coolant being too low: ↓ Add antifreeze or replace the coolant.	*BF20.00-P-1001-04A
5	Screw tester cap (3) onto low-temperature circuit coolant expansion reservoir (2)	Test cap	Fig 3
6	Connect pressure pump (4) at tester cap (3)	Pressure pump	Fig 2
7	Apply compressed air to low-temperature circuit for 2 minutes at the test pressure	Do not exceed the specified test pressure. Damage can occur on the engine cooling system otherwise. There should be no loss of pressure within a period of 2 minutes.
		Test pressure for pressure-testing cooling system	*BE20.30-P-1005-01A
8	Perform a visual inspection on the components carrying coolant	In the event of pressure loss: Check condition and coolant loss for all coolant carrying components and connections.
	Install
9	Actuate pressure relief button on pressure pump (4) and relieve the pressure	Pressure pump	Fig 2
10	Unscrew tester cap (3) at low-temperature circuit coolant expansion reservoir (2)	Test cap	Fig 3
11	Switch off ignition
12	Check coolant level and antifreeze content coolant	If necessary
		Coolant mixing ratio	*BF20.00-P-1001-04A
13	Screw cap (1) onto low-temperature circuit coolant expansion reservoir (2)
14	Install engine cover

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

Courtesy of MERCEDES-BENZ USA

Fig 3: Identifying Test Cap (210 589 00 91 00)

Courtesy of MERCEDES-BENZ USA