Remove/install coolant thermostat

AR20.10-S-2461PD

Remove/install coolant thermostat

22.11.2019

Model

470, 471 with engine 699

Modification notes

12.09.2019

Work procedure changed.

Operation steps 1, 2

12.09.2019

Method extended

Step 9

19.11.2019

Information added.

Operation step 3

19.11.2019

Method extended

Operation step 7

Shown with engine 699.304/305

1

Coolant thermostat

4

Electrical connector

7

Vacuum line

2

Screw

5

Coolant hoses

8

Electrical wiring harness

3

Electrical wiring harness

6

Clip

 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 avoiding damage through contamination and foreign objects

AH00.00-P-5000-01A

Topical note

Information on preventing damage to electronic components due to electrostatic discharge

AH54.00-P-0001-01A

 

Remove/install

1.1

Remove automatic transmission.

Model 470, 471 with engine 699 with transmission 700.770

AR27.10-S-0500P

1.2

Remove manual transmission.

Model 470, 471 with engine 699 with transmission 700.780

AR26.10-S-0021PU

2

Drain off coolant.

AR20.00-S-1142P

3

Remove clamps (6) with coolant hoses (5) from the coolant thermostat (1).

 Collect escaping coolant using suitable vessel.

 Installation: Check clamps (6) for damage. Position clamps (6) correctly.

 Commercially available devices/tools
Hose clamp pliers with wire cable

If damage is present,



replace the affected clamp (6).

4

Disconnect electrical connection (4).

5

Remove electrical wiring harness (3) from the coolant thermostat (1).

6

Remove vacuum line (7) from the coolant thermostat (1).

7

Remove electrical wiring harness (8) from the coolant thermostat (1).

Model 470 with engine 699.304/305

 Installation: Check retaining clips for damage.

Depending on the findings,



Replace retaining clip.

8

Remove coolant thermostat (1).

 To do this, remove screws (2).

 Installation: Check sealing ring for damage.

 Screw/bolt, coolant thermostat to crankcase

*BA20.10-N-1003-01PD

If damage is present:



Replace sealing ring.

9

Install in the reverse order.



Check

10

Check engine cooling system for leak tightness.

AR20.00-S-1011P

 Auxiliary coolant pump, coolant pump, coolant thermostat, belt pulley

Number

Designation

Model 470, 471 with engine 699

BA20.10-N-1003-01PD

Screw/bolt, coolant thermostat to crankcase

Nm

11