Power units
Filling shut-off device
The reducing agent tank in the Polo is equipped with a filling shut-off device due to its design and installation
position. It consists of a plastic float that is mounted so it can move inside a guide cylinder leading to the
breather line connection.
Function
When you fill the reducing agent tank with AdBlue®, the air escapes from the tank via the breather line.
Refilling procedure at low filling speed
Breather line
If you fill the reducing agent tank slowly, for
example, with a refill bottle, the float will rise slowly
with the AdBlue® level.
Float
The float will close the breather line when it reaches
the top position. The air then escapes from the tank
slowly via small notches in the float.
Filler pipe
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Notch
Filling procedure at high filling speed
Breather line
Float
If you fill the reducing agent tank at a high speed, for
example, with an AdBlue® filling nozzle, this will lead
to strong wave movements in the tank. The float will
rise quickly due to the wave movement thus closing
the breather line early. This reduces the risk of
AdBlue® leaking due to the considerably higher
filling speed.
Filler pipe
As soon as the AdBlue® level has settled after the
filling nozzle automatically shuts off, the float will be
lowered and open the breather line again. The filling
quantity can be increased slightly by actuating the
filling nozzle repeatedly.
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