Inspect cooling system for leaks

AR20.00-P-1010CW

Inspect cooling system for leaks

05.12.2018

Engine

271 in model 212

Engine

271, 272, 273, 642, 651 in model 207

Engine

271, 272, 642, 646, 651 in model 204

Engine

271, 651 in model 172

Engine

642 in model 212

*

Engine

651 in model 212

*

Modification notes

15.06.2010

Scope of testing added

Operation step 7

Shown on engine 642 in model 212

1

Cap

2

Expansion reservoir

3

Tester cap

4

Pressure pump



Check

 Warning

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

Topical note

Notes on coolant

AH20.00-N-2080-01A

1

Adjust heater to maximum heat output

2

Unscrew cap (1) slowly at expansion reservoir (2) and relieve overpressure

3

Check coolant level

Notes on coolant level

AH20.00-P-1142-01CW

 Coolant mixing ratio

*BF20.00-P-1001-04A

4

Screw on tester cap (3) at the expansion reservoir (2)

 Test cap

*210589009100

5

Connect pressure pump (4) at tester cap (3)

 Pressure pump

*124589242100

6

Apply test pressure to cooling system


The specified test pressure must not be exceeded.
Damage can occur to the cooling system otherwise.

Test pressure for pressure-testing the engine cooling system

*BE20.30-P-1005-01A

7

Perform visual inspection on coolant carrying components

Open and close Henn coupling

AR09.41-P-1311-01AL


Check condition and seating of the Henn coupling.
See: 
Replace catch spring as necessary to avoid coolant loss.

 Check condition and coolant loss for all coolant carrying components and connections. The coolant carrying components should be checked for inner leaktightness if there is no external coolant loss. There is the possibility, for example, that coolant can find its way over a defective cylinder head gasket into the combustion chamber or over a defective heat exchanger into the oil circuits.

8

Relieve test pressure in cooling system

 To do this actuate pressure relief button on the pressure pump (4).

 Pressure pump

*124589242100

9

Detach pressure pump (4) on tester cap (3)

 Pressure pump

*124589242100

10

Unscrew test cap (3) at the expansion reservoir (2)

 Test cap

*210589009100

11

Check coolant level and antifreeze content coolant

Notes on coolant level

AH20.00-P-1142-01CW

 Coolant mixing ratio

*BF20.00-P-1001-04A

12

Screw cap onto expansion reservoir (2)

Radiator or expansion reservoir cap

Number

Designation

1-stage cover latch

Engine 100, 102, 103, 104, 110, 111, 112, 113, 114, 115, 116, 117, 119, 120, 121, 123, 127, 129, 130, 133, 137, 139, 152, 155, 156, 157, 159, 166, 180, 256, 260, 264, 266, 270, 271, 272, 273, 274, 275, 276, 277, 278, 279, 282, 285
2-stage latch cover
Engine 601, 602, 603, 604, 605, 606, 607, 608, 611, 612, 613, 615, 616, 617, 621, 626, 628, 629, 640, 642, 646, 648, 651, 654, 656, 668
2-stage latch cover

BE20.30-P-1005-01A

Test pressure for pressure-testing the engine cooling system

Overpressure

bar

1,4

1,4

 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