Cooling System Components Overview, Engine Side

Cooling System Components Overview, Engine Side


Hot steam may escape when opening the expansion tank cap. Wear protective goggles and protective clothing to prevent damage to eyes and scalding. Cover the cap with a cloth and carefully open the cap.

• When the engine is warm the cooling system is under pressure. The pressure must be released, if necessary, before repairing

• Secure all hose connections using hose clamps appropriate for the model type.

• Hose clip pliers (V.A.G 1921) or spring type clip pliers (VAS 5024 A) are recommended for installing spring clamps.

• Replace the gaskets and seals.

• The arrows on the coolant pipes and coolant hoses must line up across from each other.

• Make sure when replacing the expansion tank and for maintenance work that there is always a silicate cartridge in the expansion tank, refer to the Parts Catalog. The silicate cartridge must not be removed.






1 Bolt

• 40 Nm

2 Bolt

• 23 Nm

3 Coolant Line

4 Connecting Hose

5 O-ring

• Always replace.

6 Water Connection

7 Bolt

• 10 Nm

8 Retaining Clip

9 O-ring

• Always replace.

10 Engine Coolant Temperature Sensor (G62)

11 Connecting Hose

12 Distributor Piece

13 Connecting Hose

14 Connecting Hose

15 Connecting Hose

16 Coolant Line

• Removing and installing, refer to => [ Coolant Pipes ] Coolant Pipes.

17 Bolt

• 5 Nm

18 Connecting Hose

19 Coolant Line

• Removing and installing, refer to => [ Coolant Pipes ] Coolant Pipes.

20 Bolt

• 10 Nm

21 Coolant Thermostat Housing with Coolant Thermostat

• Coolant thermostat checking, refer to "Function and Component Selection" in the vehicle diagnostic tester

• Opening begins at 87 °C (188.6 °F).

22 Bolt

• 15 Nm

23 Coolant Pump

• Removing and installing, refer to => [ Coolant Pump ] Service and Repair.

24 Bolt

• 15 Nm