AUDI A4 2000 B5 / 1.G APB Engine Cooling System Components

19-1


Cooling system components,
removing and installing

WARNING!

Hot steam can escape from the expansion
tank when the filler cap is opened. Cover the
filler cap with a cloth and unscrew it carefully.

Notes:

When the engine is hot the cooling system is
under pressure. Carefully open filler cap on
expansion tank to release pressure before
starting repair work.
Hoses are secured with spring-type clips. When
repairing only use spring-type clips.
VAG 1921 pliers are recommended when
installing spring-type clips.
The O-rings fitted at the quick-release
connections must be replaceed if damaged or
leaking.
When installing coolant hoses, ensure that they
are free of stress and do not come into contact
with other components (observe markings on
coolant connection and hose).
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Perform leak test on cooling system with cooling
system tester VAG 1274 and adapter VAG
1274/8.
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19-2

Cooling system components (on body),
removing and installing


Notes:

Parts of cooling system on engine Page 19
-
8 .

Diagram of coolant hose connections Page 19
-17
.

Draining and filling with coolant Page 19
-
19
.

Coolant mixture ratios Page 19
-19
, draining
and filling cooling system.
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19-3


1 -
Radiator
Removing and installing Page 19
-26
After replacing, replace coolant in complete
system
2 -
Securing clip
3 -
Securing rubber
4 -
O-ring Replace if damaged
5 -
Bottom coolant hose Secured to radiator with retaining clipCheck for secure seatingDiagram of coolant hose connections
Page 19
-17

6 -
Rubber washer
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19-4


7 -
Retaining bolt
8 -
Nut
Tightening torque: 10 Nm
9 -
Fan ring Clipped into air ducting and secured with
retaining bolt -Item 7 -
10 -
2-pin connector
11 -
Radiator fan (-V7-)
12 -
Connector Black, 3-pinFor radiator fan thermoswitch
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19-5


13 -
Radiator fan thermoswitch (-F18-), 35 Nm
For electric fan
Switching temperatures: Stage 1on: 92...97 Coff: 84...91 C
Switching temperatures: Stage 2
on: 99...105 Coff: 91...98 C
14 -
Seal
Always replace
15 -
Drain screw Tightening torque: 10 Nm
16 -
Top coolant hose Secured to radiator with retaining clipCheck for secure seatingDiagram of coolant hose connections
Page 19
-17

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19-6


17 -
Bolt
Tightening torque: 5 Nm
18 -
Mounting rod
19 -
Guard plate
20 -
Bolt Tightening torque: 5 Nm
21 -
Bolt Tightening torque: 5 Nm
22 -
Radiator Removing and installing Page 19
-26
After replacing, replace coolant in complete
system
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19-7


23 -
Nut
Tightening torque: 5 Nm
24 -
Bracket
25 -
Fan ring
26 -
Pressurizing fan
27 -
Bolt Tightening torque: 5 Nm
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19-8


Cooling system components (on engine,
front), removing and installing

1 -
Connection
For thermostat
2 -
O-ring Always replace
3 -
Thermostat Checking: heat the thermostat in waterStarts to open at about 86 COpening travel: at least 7 mm
4 -
Bolt Tightening torque: 10 Nm
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19-9


5 -
Filler cap
Test with cooling system tester VAG 1274
and adapter VAG 1274/9 Test pressure 1.4...1.6 bar
6 -
O-ring Replace if damaged
7 -
Bolt Tightening torque: 10 Nm
8 -
Expansion tank Carry out leak test of cooling system with
cooling system tester VAG 1274 and
adapter VAG 1274/8
9 -
To rear water line Diagram of coolant hose connections
Page 19
-17

Pa
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g system com
ponents, removin
g and installin
g
11/21/2002 htt
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yp
e=re
pair&id=AUDI.B5.GE05.19.1