Inspect cooling system for leaks

AR20.00-P-1010AK

Inspect cooling system for leaks

11.12.2018

Engine

266.920/940/960/980 in model 169.0/3, 245.2

Shown on model 169.0 with engine 266.920

1

Coolant expansion reservoir

2

Tester cap

3

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

Open hood

2

Open cap on coolant expansion reservoir (1)

 Rotate half a revolution counterclockwise, release overpressure and then unscrew cap.

3

Check coolant level; adjust to correct level if necessary

Notes on coolant level

AH20.00-P-1142-01CW



Coolant specifications

BB00.40-P-0310-01A



Anticorrosion/antifreeze agents (Sheet 325.0)

BB00.40-P-0325-00A

4

Mount tester cap (2) on coolant expansion reservoir (1)

 Test cap

*169589009100

5

Connect pressure pump (3)

 Pressure pump

*124589242100

6

Pressurize cooling system

 With a new cylinder head gasket: check cooling system for leak tightness once the engine has reached operating temperature.

Test pressure for pressure-testing the engine cooling system

*BE20.30-P-1005-01A

 Test cap

*169589009100

 Pressure pump

*124589242100

7

Check cooling and heating hoses as well as their connections for proper condition and coolant loss, check condition and seating of hose clamps

8

Remove pressure pump (3) and tester cap (2)

 Test cap

*169589009100

 Pressure pump

*124589242100

9

Close cap on coolant expansion reservoir (1)

10

Close engine hood

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