Volkswagen Golf Diesel 2009 Mode D'emploi page 278

Coolant Pump
The coolant pump, temperature sensor, and coolant
thermostat are integrated in a common housing
made of duroplastic.
This housing is attached to the cylinder block below
the intake manifold.
A drive gear at the end of the balance shaft drives
the coolant pump via a toothed belt. The larger drive
gear on the pump acts as a speed reducer. A fan
wheel is attached to the coolant pump drive gear to
cool the toothed belt.
The coolant pump impeller is made of plastic and has
a special vane contour which permits high engine
speeds with low risk of pump cavitation.
The thermostat begins to open at 203°F (95°C) and
is fully open at 221°F (105°C).
Engine Coolant
Temperature (ECT)
Sensor G62
Heating
Return Line
Coolant
Thermostat
Balance
Shaft
Outlet
Note
Inlet
Cooling System
The tension of the coolant pump
drive belt is defi ned by the installation
position of the coolant pump and
cannot be adjusted. In the event of
coolant pump failure, the housing
must also be replaced.
The toothed belt drive gear of the
coolant pump has a left-hand thread.
Coolant Pump
Impeller
Toothed Belt Drive
Gear with Left-Hand
Thread Bolt
Fan Wheel
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