Cooling System Components, Engine Side, Assembly Overview

Cooling System Components, Engine Side, Assembly Overview

• Coolant Hose Connection Diagram. Refer to => [ Coolant Hose Connection Diagram ] [1][2]Cooling System.

• Vehicles with an automatic transmission have a by-pass thermostat in the coolant supply hose to the transmission fluid cooler.

By-pass thermostat - assembly overview => [ By-pass thermostat - assembly overview ].

By-pass thermostat, checking






1 To top of the coolant reservoir

2 Coolant connections on the heat exchanger

3 O-ring

• Replace

4 Connector

• For the engine coolant temperature sensor (G62)

• 2-pin

5 Coolant temperature sensor (G62)

6 Retaining clip

• Make sure it is secure

7 From transmission oil cooler

• Only vehicles with automatic transmission

8 40 Nm

9 Coolant line

10 9 Nm

11 O-ring

• Replace

12 Coolant Distribution Housing

13 To transmission oil cooler

• Only vehicles with automatic transmission

14 from lower reservoir

15 Prewarmer

• not installed on all vehicles

• Assembly overview => [ Engine Pre-Heater Assembly Overview ] Service and Repair

16 To the upper radiator connection

17 To the upper radiator connection

18 From the lower radiator connection

19 Engine oil cooler

20 15 Nm

21 Connecting piece

22 Coolant thermostat

• Checking: Heat up thermostat in water

Starts to open: approximately 86 °C

Opening lift: at least 7 mm

• Removing and Installing, refer to => [ Coolant Thermostat, Removing and Installing ] Service and Repair

23 Toothed belt

• Mark direction of rotation before removing

• Check for wear

• Do not kink

• Removing and Installing, refer to => [ Toothed Belt, Removing and Installing ] Service and Repair

24 Coolant pump

• Check for ease of movement

• Replace completely if damaged or leaking

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

25 15 Nm

26 Rear toothed belt guard

27 20 Nm

28 Throttle valve control module (J338)

By-pass thermostat - assembly overview





1 Spring bracket
2 Lower part of housing
Note installation position: Arrow points toward ATF cooler
3 Operating element
4 Spring
5 O-ring
6 Upper part of housing

Checking bypass thermostat

- Remove operating element - 3 - and heat in a hot water bath.

Starts to open: approximately 75 °C

Opening end: approximately 85 °C

Opening lift: approximately 5 mm