17 00 039 Venting and filling cooling system with vacuum filling unit: Preconditions
- Cooling system expansion tank must be empty.
- There must be sufficiently premixed coolant in the filling unit container, 1-2 liters more than the vehicle filling capacity.
- Observe filling capacities. See COOLING SYSTEM - TECHNICAL DATA .
Use only recommended coolant. Observe mixture ratio. See RADIATOR - OPERATING FLUIDS .
- Position the filling unit container at the same height as the coolant expansion tank.
- Compressed-air connection with 6 bar pressure present.
- Set vehicle heater to maximum temperature.
Select adapter (Y) according to table and connect to coolant expansion tank.
Connect filler unit to adapter connection (X).
Shutoff valves (A) and (B) of the filling unit (1) must be closed.
(X) Expansion tank connection
Connect venturi nozzle (1) to filling unit (2).
(X) Expansion tank connection
Connect compressed air (1).
(X) Expansion tank connection
Open shutoff valve (B).
The venturi nozzle produces a flow noise.
Then open shutoff valve (A) until the filling hose (1) is free of bubbles.
Close shutoff valve (A) again. The filling hose (1) is vented in this way.
Shutoff valve (B) remains open. Generate vacuum in coolant system for approx. 2 minutes. The end vacuum is reached at a vacuum of -0.7 to -0.95 bar. Green scale on the vacuum meter.
Then close shutoff valve (B) again.
Both shutoff valves (A) and (B) must be closed.
Then seal Venturi nozzle (1).
The cooling system must hold the vacuum for 30 s. If the needle in the vacuum meter falls, this indicates a leak in the cooling system.
If the vacuum remains constant, proceed with filling.
In event of leaks, check cooling system for leaks.
Position the filling unit container at the same height as the coolant expansion tank.
Shut-off valve (B) remains closed during the filling process.
To fill the cooling system, open shutoff valve (A) to filling unit container.
Coolant is now added.
The filling procedure is finished when the needle in the vacuum meter is at 0 bar or no longer falls.
If necessary, reduce remaining vacuum. Open shutoff valve (B) to do so.
Remove filling unit with adapter from expansion tank.
Adjust coolant level to maximum.
Close coolant expansion tank.