Inspecting cooling system for leaks · ar2000w1010r · Mercedes-Benz WIS

AR20.00-W-1010R

Inspecting cooling system for leaks

13.12.11

ENGINES 926.9 in MODEL 949

W20.00-1038-12

1 Expansion reservoir

2  Clamp

3  Adapter

4  Testing unit

5  Angled piece

6  Knurled nut

	Checking
1	Open engine hood and move to vertical position		AR88.40-W-1000R
 Danger!	Risk of injury to skin and eyes caused by scalding from contact with hot coolant spray. Risk of poisoning caused by 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
2	Unscrew cap from coolant expansion reservoir (1)
	Notes on coolant		AH20.00-N-2080-01A
3	Check coolant level, pour in coolant if necessary	 If the antifreeze in the coolant is too low, either add more antifreeze or change the coolant.
			*BF20.00-N-1001-01C
4	Rub dry inside of coolant filler neck at the expansion reservoir (1)
5	Turn rubber seal on adapter (3) until it fits the inside diameter of the coolant filler neck		*655589006300
6	Screw off knurled nut (6) on adapter (3)
7	Tighten angular piece (5) and testing unit (4) on the adapter (3)		*001589832100
8	Attach adapter (3) with testing unit (4) to expansion reservoir (1) and hook clamp (2) with the knurled nut (6) on adapter (3)		*950589126300
9	Hook in clamp (2) under raised bead (arrows) on coolant filler neck and secure with knurled nut (6).
10	Apply compressed air to cooling system at testing unit (4) and check cooling system for leaks	 Observe test pressure and test period since otherwise damage may occur to the cooling system.	*BE20.30-N-1001-01F
		 A pressure drop at the pressure gauge of the testing unit (4) is visible in case of leaks in the cooling system.
11	Perform visual inspection on all coolant carrying components	 Only in the case of a pressure drop and visible coolant loss: 
		Check radiator, heater, coolant pump, cooling and heating hoses, coolant lines and their connecting points, hose clamps, cylinder head gasket, core hole cap or core hole plug screws; remove leaks in cooling system.
		In case of pressure drop and no visible coolant loss: 
		Check cylinder head for cracks.
12	Release test pressure on the testing unit (4), remove clamp (2) and remove adapter (3) with testing unit (4) from expansion reservoir (1)
13	Check coolant level, pour in coolant if necessary	 Only if there was a pressure drop in the cooling system.
		If antifreeze in the coolant is too low, either add more antifreeze or change the coolant.
			*BF20.00-N-1001-01C
14	Tighten cap on expansion reservoir (1)
15	Close engine hood		AR88.40-W-1000R

Check values for cooling system

Number	Designation			Engine 900.9, 902.9, 904.9, 906.9, 924.9, 925.9, 926.9


BE20.30-N-1001-01F	Permissible pressure drop in cooling system	Test pressure 1.0 bar, test period 5 to 10 min	bar	0

 Engine cooling system

Number	Designation			Engine 926.9 in model 949.0


BF20.00-N-1001-01C	Coolant	Total filling capacity	l	22
		Anticorrosion/antifreeze agent down to -37°C	l	11
		Anticorrosion/antifreeze agent down to -45°C	l	12.0
		Specifications for Operating Fluids	Sheet	BB00.40-P-0310-01A
			Sheet	BB00.40-P-0325-02A
			Sheet	–

655 589 00 63 00

Clamp

Adapter

Tester

001 589 83 21 00

950 589 12 63 00

Referenced documents

ah2000n208001a Notes on coolant
ar8840w1000r Opening engine hood, moving to upright position and closing
as2000z000101a Risk of injury to skin and eyes suffering scalding from contact with hot coolantspray. Risk of poisoning from swallowing coolant.