Drain/fill coolant for cooling electric motor

AR08.50-S-0020F

Drain/fill coolant for cooling electric motor

24.07.2020

Engine

780.701/702 in model 447

Modification notes

19.02.2020

Method extended

Operation step 3.2

19.02.2020

Information added

Operation step 29

20.07.2020

Special tool 124 589 24 21 00 pressure pump added.

Operation step 25

20.07.2020

Method modified.

Operation steps 36, 40, 41, 42, 43, 44, 45

AR08.50-S-0017-01F

20.07.2020

Special tool 124 589 24 21 00 pressure pump added.

Operation steps 40, 41, 43, 44

AR08.50-S-0017-01F

Shown with engine 780.701

1

Cap

2

Coolant expansion reservoir

Shown with engine 780.701

3

Hose

5

Radiator

4

Drain screw

Shown with engine 780.701

6

Coolant hose line

8

Electric motor

9

Coolant hose line

7

Coolant line

Shown with engine 780.701

2

Coolant expansion reservoir

10

Tester cap

11

Pressure pump

 Danger

Risk of death when working on component parts and systems with U >= 30 V alternating voltage (AC) or U >= 60 V direct voltage (DC)

Do not touch damaged or defective live component parts and lines or non-insulated electrical connections and lines.

AS00.00-Z-0035-01A

 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

General information on vehicles with high-voltage on-board electrical system and/or lithium-ion battery and/or gaseous-fuel drive system as well as personal protective equipment

AH00.00-Z-0300-01A

Topical note

Notes on avoiding damage through contamination and foreign objects

AH00.00-P-5000-01A

Topical note

Notes on coolant

AH20.00-N-2080-01A

Notes on coolant level for electric motor cooling system

AH08.50-S-0050-01F

Drain off

1

Lock electric coolant pumps using vehicle diagnosis system.



Connect STAR DIAGNOSIS and read out fault memory

AD00.00-S-2000-04E


HVAC system must be deactivated (position 0).
Coolant pumps will otherwise be actuated in an unintended manner, which can cause malfunctions.

 Work through specified procedure completely.
To do so, select following menu items:
Powertrain (CPC) 
Actuations 
Locking of coolant pumps.

 Do not yet remove vehicle diagnosis system.

2

Remove cap (1) of coolant expansion reservoir (2).

 First unscrew cap (1) counterclockwise to first detent and release overpressure. Then remove cap (1).

3.1

Raise vehicle.

Engine 780.701 in model 447

AR00.60-S-1000E

3.2

Remove bottom engine compartment paneling.

Engine 780.702 in model 447

AR61.20-S-1105E

4

Push a suitable hose (3) onto fitting (arrow A) on cooler (5).

5

Unscrew drain screw (4) until coolant drains off.

 Collect coolant.
Commercially available devices/tools
Collecting pan

6

Replace sealing ring at drain screw (4).

If drain screw (4) was leaky.

 Assembly tool

*000589936300

7

Lower vehicle.

8

Attach tester cap (10) to coolant expansion reservoir (2).

 Test cap

*210589009100

9

Attach pressure pump (11) to the tester cap (10).

 Test cap

*210589009100

 Pressure pump

*124589242100

10

Use pressure pump (11) to generate pressure until coolant no longer escapes.


The cooler (5) must be as empty as possible.
Otherwise, filling and later ventilation cannot be performed completely, which can lead to malfunctions and damage.

 Collect coolant.
Commercially available devices/tools
Collecting pan

 Pressure pump

*124589242100

11

Raise vehicle.

12

Screw in drain screw (4).

 Drain screw to cooler for electric motor cooling

*BA08.50-N-1001-01F

13

Pull hose (3) off fitting (arrow A) on cooler (5).

14

Remove coolant hose line (6) from coolant line (7) and drain coolant.

AR20.20-P-7441-01RQ

 Collect coolant.
Commercially available devices/tools
Collecting pan

15

Remove coolant hose line (9) from electric motor (8) and drain coolant.

AR20.20-P-7441-01RQ

 Collect coolant.
Commercially available devices/tools
Collecting pan

16

Lower vehicle.

17

Use pressure pump (11) to generate pressure until coolant no longer escapes.


The cooler (5) must be as empty as possible.
Otherwise, filling and later ventilation cannot be performed completely, which can lead to malfunctions and damage.

 Collect coolant.
Commercially available devices/tools
Collecting pan

 Pressure pump

*124589242100

18

Raise vehicle.

19

Reattach coolant hose line (6) to coolant line (7).

AR20.20-P-7441-01RQ

20

Reattach coolant hose line (9) to electric motor (8).

AR20.20-P-7441-01RQ

21

Lower vehicle.

22

Remove pressure pump (11).

 Pressure pump

*124589242100

Pour in

23

Put the high-voltage on-board electrical system into operation.

If the high-voltage on-board electrical system is not in operation.

Engine 780.701 in model 447

AR47.70-S-1000F

Engine 780.702 in model 447

AR47.70-S-1000G

24

Attach charger to 12 volt on-board electrical system battery.

AR54.10-S-1127E

 The filling and bleeding of the coolant circuit using the vehicle diagnosis system takes some time. A constant 12 volt power supply is required for this purpose.

25

Fill coolant into coolant circuit of electric motor (8).

AR08.50-S-0017-01F


The coolant circuit must be as empty as possible before filling.
Otherwise, filling and later ventilation cannot be performed completely, which can lead to malfunctions and damage.

 Evacuate, check and fill coolant circuit.

 Electric drive cooling system

*BF08.50-N-1001-01F

 Test cap

*210589009100

 Cooler vacuum filling device

*285589002100

 NTKL Adaption

*285589012100

 Electric vacuum pump

*285589022100

 Pressure pump

*124589242100

26

Bleed coolant circuit for electric motor (8) using the vehicle diagnosis system.



Connect STAR DIAGNOSIS and read out fault memory

AD00.00-S-2000-04E

AR08.50-S-0017-01F

 Coolant pumps are automatically released during bleed process.
Work through specified procedure completely.
To do so, select following menu items:
Powertrain (CPC) 
Special procedures 
Bleeding of coolant circuit for electric drive

 Duration of bleed process of coolant circuit for electric drive is approx. 15 min.

27

Remove charger from 12 volt on-board electrical system battery.

AR54.10-S-1127E



Check

28

Check coolant level of the coolant circuit of the electric motor (8).

If coolant level incorrect



Correct coolant level.

 Electric drive cooling system

*BF08.50-N-1001-01F

29

Check the coolant circuit of the electric motor (8) for leak tightness.

AR08.50-S-0010F

 Engine 780.702 in model 447
Reinstall lower engine compartment lining after leak test.

 Cooling system

Number

Designation

Engine 780.701/702 in model 447

BA08.50-N-1001-01F

Drain screw to cooler for electric motor cooling

Nm

 3

 Cooling system

Number

Designation

Engine 780.701/702 in model 447

BF08.50-N-1001-01F

Electric drive cooling system

Cooling system of high-voltage battery and vehicle interior

Filling capacity

Liter

 10

Cooling system of electric motor

Filling capacity

Liter

 5

For both cooling systems, entire filling capacity, in the workshop

Filling capacity

Liter

 15

Antifreeze/water

Down to -37 °C

%

50/50

Coolant specifications

BB00.40-P-0310-01A

Sheet

BB00.40-P-0325-05A