Inspect cooling system for leaks

AR20.00-P-1010RKC

Inspect cooling system for leaks

12.11.2018

Engine

279 in model 231

Modification notes

26.09.2014

Mixing ratio for coolant

BF20.00-P-1001-04A

1

Cap

2

Coolant expansion reservoir

3

Tester cap

4

Pressure pump



Remove

 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

Switch on ignition

2

Adjust heater to maximum heat output

3

Unscrew cap (1) on coolant expansion reservoir (2)


Slowly unscrew cap (1) on coolant expansion reservoir (2) and relieve overpressure.
Scolding can occur otherwise through spitting out of hot coolant.

4

Check coolant level and antifreeze content coolant

 If antifreeze content of coolant is too low, either antifreeze protection must be added or the coolant must be replaced.

 Coolant mixing ratio

*BF20.00-P-1001-04A

5

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

 Test cap

*210589009100

6

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

 Pressure pump

*124589242100

7

Apply test pressure to cooling system

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

Test pressure for pressure-testing the engine cooling system

*BE20.30-P-1005-01A



Check

8

Perform visual inspection on coolant carrying components

AR09.41-P-1311-01AL


The catch springs for the Henn coupling must be checked for their condition and seat and replaced if necessary.
Coolant loss can occur otherwise.

 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 water heat exchanger into the oil circuits.



Install

9

Remove overpressure over the valve at the pressure pump (4) and remove pressure pump (4)

 Pressure pump

*124589242100

10

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

 Test cap

*210589009100

11

Switch off ignition

12

Check coolant level and antifreeze content coolant

Notes on coolant level

AH20.00-P-1142-01CW

 Coolant mixing ratio

*BF20.00-P-1001-04A

13

Screw cap (1) 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