Audi A8 2003 Workshop Manual page 225

8-cylinder TDI engine (4.2 ltr. 4-valve common rail), mechanics - Edition 12.2013
– Open valve -B- by setting lever in direction of flow.
The suction jet pump generates a partial vacuum in the cooling
system.
• The needle on the gauge should move into the green zone.
– Also briefly open valve -A- (turn lever in direction of flow) so
that hose on charge unit reservoir -VAS 6096- can fill with
coolant.
– Close valve -A- again.
– Leave valve -B- open for another 2 minutes.
• The suction jet pump will continue generating a vacuum in the
cooling system.
• The needle on the gauge should remain in the green zone.
– Close valve -B-.
• The needle on the gauge should stop in the green zone. The
vacuum level in the cooling system is then sufficient for sub‐
sequent filling.
If the needle does not reach the green zone, repeat the process.
If the vacuum level drops, there is a leak in the cooling system.
– Detach compressed air hose.
– Open valve -A-.
The vacuum in the cooling system causes the coolant to be drawn
out of the reservoir for cooling system charge unit -VAS 6096- ;
the cooling system is then filled.
– Detach cooling system charge unit - VAS 6096- from expan‐
sion tank.
– Carefully pull engine cover panel off four retaining pins one
after the other -arrows-.
– Unscrew bleeder screw -arrow-.
– Fill up with coolant until it flows out at bleeder hole free of
bubbles.
– Close bleeder screw.
– If fitted, unscrew bleeder screw on radiator and fill up with
coolant until it comes out at bleeder screw.
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with respect to the correctness of information in this document. Copyright by AUDI AG.
1. Removing and installing parts of cooling system
Audi A8 2003 ➤
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