Cooling System Components (on Engine), Assembly Overview
Cooling system components (on engine), assembly overview
Note: For vehicles in countries with high outside temperatures, an electrical After-run coolant pump -V51- is also installed.
1 - Connecting piece
^ For thermostat
2 - O-ring
^ Replace
3 - Coolant thermostat
^ Checking: Heat up thermostat in water
- Opening begins: approx. 86° C Opening ends: approx. 102° C Open distance: at least 7 mm
^ Observe installed location
4 - Bleeder screw, 20 Nm
5 - 22 Nm
6 - Retaining clip
^ Check for secure seating
7 - Engine Coolant Temperature (ECT) sensor -G62-
^ For engine control module
^ If necessary release pressure in cooling system before removing
8 - Rear coolant pipe
^ Only on vehicles with engine codes AHA and ATQ with connection for throttle valve control module
9 - Lifting eye
10 - 10 Nm
11 - Coolant line
12 - Front coolant line
13 - Cap
^ Check using cooling system tester V.A.G 1274 and adapter V.A.G 1274/9
^ Pressure relief valve must open at a pressure of 1.4 to 1.6 bar
14 - Oil seal
^ Replace if damaged
15 - Reservoir
^ Check using cooling system tester V.A.G 1274 and adapter V.A.G 1274/8
16 - Upper coolant hose
^ Ensure seated tightly
^ Secured to radiator with a retaining clip
17 - Coolant line
18 - Rear toothed belt cover
19 - Seal
^ Replace
20 - Coolant pump
^ Check for ease of movement
^ If damaged or leaking replace completely
21 - Lower coolant line
22 - Oil cooler
23 - Pulley
^ For viscous fan clutch
24 - Fan wheel
25 - Viscous fan clutch
^ Be aware of left-handed thread
^ Tightening torque only valid when using open end wrench 3312.
^ Fasten to 40 Nm
26 - Bracket
^ For viscous fan clutch
27 - From lower radiator
^ Coolant hose connection diagram
After-run coolant pump -V51- - arrow -
Function
The After-run coolant pump -V51- is generally activated approx. 15 seconds after switching off the ignition and runs for 10 to 12 minutes. If coolant temperature is above 92° C during this time, Coolant fan -V7- is also switched on.