Inspect cooling system for leaks

AR20.00-S-1010S

Inspect cooling system for leaks

12.11.2018

Engine

112, 272, 642, 646, 651 in model 639

Engine

271.951, 272.979, 642.896/898/992/993, 646.984/985/986/989/990, 651.955/956/957 in model 906

Engine

272, 646, 651 in model 636

Engine

651 in model 900

Shown on model 639

1

Expansion reservoir

2

Tester cap

3

Pressure pump

 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

Notes on coolant level

AH20.00-P-1142-01CW

 

Remove/install

1

Set heater switches to maximum heat output

2

Switch auxiliary heater to full output

Model 636, 639 with code H12 (Auxiliary heater (hot water)) Model 636, 639 with code H13 (Additional heat exchanger in passenger compartment) Model 900, 906 with code H12 (Auxiliary heater (hot water)) Model 900, 906 with code H13 (Additional heat exchanger in cargo area)

3

Open expansion reservoir (1)

 Turn cap on the expansion reservoir (1) anti-clockwise by half a revolution, release overpressure, then unscrew the cap.

4

Check coolant level; correct if necessary



Coolant specifications

BB00.40-P-0310-01A



Anticorrosion/antifreeze agents (Sheet 325.0)

BB00.40-P-0325-00A

5

Screw tester cap (2) onto expansion reservoir (1)

 Test cap

*639589009100

6

Connect pressure pump (3) at tester cap (2)

 Pressure pump

*124589242100

7

Apply test pressure to cooling circuit

Engine 112 in model 639 Engine 272 in model 636, 639Test pressure

*BE20.30-N-1004-01A

Engine 271, 272, 642, 646 in model 906 Engine 642 in model 639 Engine 646 in model 636, 639 Engine 651 in model 636, 639, 900, 906Test pressure

*BE20.30-N-1004-01B

8

Remove bottom engine compartment paneling

MODEL 636 MODEL 639.7##/8## ## as of 055347

AR61.20-S-1105S



Check

9

Check coolant hoses as well as their connections for proper condition and coolant loss; seal, if necessary

10

Install in the reverse order

Check values for cooling system cap

Number

Designation

Engine 112.951/976, 272

BE20.30-N-1004-01A

Test pressure

bar

1,5

Check values for engine cooling system cap

Number

Designation

Engine 271, 272, 642, 646 in model 906

Engine 642 in model 639

BE20.30-N-1004-01B

Test pressure

bar

1,5

1,5

Check values for engine cooling system cap

Number

Designation

Engine 646 in model 636, 639

Engine 651 in model 636

BE20.30-N-1004-01B

Test pressure

bar

1,5

1,5

Check values for engine cooling system cap

Number

Designation

Engine 651 in model 639

Engine 651 in model 900, 906

BE20.30-N-1004-01B

Test pressure

bar

1,5

1,5