AUDI A4 1995 B5 / 1.G AHA ATQ Engines Cooling System Components Workshop Manual

19-1


Cooling system components,
removing and installing

WARNING!

The cooling system is pressurized when the
engine is warm. When opening the expansion
tank, wear gloves and other appropriate
protection, cover the cap with a cloth and
open carefully to relieve system pressure
slowly.

Notes:

Hoses are secured with spring-type clips. If
servicing, only use the same type of spring-type
clip.

Parts catalog

VAG1921 pliers are recommended when
installing spring-type clips.
The O-rings installed at the quick-release
connections must be replaced if damaged or
leaking.
Seals and gaskets must always be replaced.
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When installing coolant hoses, make sure they
are free of stress and do not come into contact
with other components (the arrows which are
located on the coolant pipes and coolant hoses
must be opposite each other).
Perform cooling system leakage test using VAG
1274 cooling system tester and 1274/9 adapter.
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19-2


Cooling system components (on body)

1 -
Radiator
Removing and installing page 19
-17
After replacing, completely replace coolantWith ATF cooler on vehicles with automatic
transmission
2 -
Securing clip
3 -
Securing rubber
4 -
O-ring Replace if damaged
5 -
Lower coolant hose Secured to radiator with retaining clipMake sure hose is securely seatedCoolant hose connection diagram page 19
-9
6 -
Securing clip
To secure temperature switch in coolant
hose
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19-3


7 -
O-ring
Replace if damaged
8 -
Coolant Fan Control (FC) thermal switch -
F18- 35 Nm (26 ft lb)For electric coolant fan
Switching temperatures, stage 1:On: 92-97 C (198-207 F)Off: 84-91 C (183-196 F)
Switching temperatures, stage 2:
On: 99-105 C (210-221 F)Off: 91-98 C (196-208 F)
9 -
Locking bolt
10 -
10 Nm (7 ft lb)
11 -
Fan ring
Clipped into air ducting and secured with
locking 9 bolt
12 -
2-pin harness connector
13 -
Coolant fan -V7- Checking page 19
-26
14 -
Rubber washer
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15 -
Coolant drain plug
10 Nm (7 ft lb)
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19-4


16 -
Upper coolant hose
Secured to radiator with retaining clipMake sure hose is securely seatedCoolant hose connection diagram page 19
-9
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19-5


Cooling system components (on engine)

1 -
Connection
For thermostat
2 -
O-ring Always replace
3 -
Coolant thermostat Removing and installing page 19
-23
Note installation position page 19
-23
Checking:
Heat thermostat in waterOpening begins at approx. 86 C (187 F)Min. opening: 7 mm (0.28 in.)
4 -
Bleeder screw 20 Nm (15 ft lb)
5 -
Bolt 25 Nm (18 ft lb)
6 -
Retaining clip Make sure clip is seated securely
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19-6


7 -
Engine Coolant Temperature (ECT) sensor
-G62-
For Engine Control Module (ECM)If necessary, release pressure in cooling
system before removing Checking Repair Manual, 2.8 Liter V6
5V Fuel Injection & Ignition, Repair Group
01
8 -
Rear coolant line
Coolant hose connection diagram page 19
-9
9 -
Lifting eye
10 -
10 Nm (7 ft lb)
11 -
Coolant line
Coolant hose connection diagram page 19
-9
12 -
Front coolant hose
Coolant hose connection diagram page 19
-9
13 -
Sealing cap
Check using VAG1274 cooling system
tester with VAG1274/8 adapter Test pressure: 1.4-1.6 bar (20-23 psi)
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19-7


14 -
O-ring
Replace if damaged
15 -
Expansion tank Check using VAG1274 cooling system
tester with VAG1274/9 adapter
16 -
Upper coolant hose Secured to radiator with retaining clipMake sure hose is securely seatedCoolant hose connection diagram page 19
-9
17 -
Coolant line
Coolant hose connection diagram page 19
-9
18 -
Rear toothed belt guard
19 -
Gasket
Always replace
20 -
Coolant pump Check for ease of movementCompletely replace if damaged or leakingRemoving and installing page 19
-20
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19-8


21 -
Lower coolant line
Coolant hose connection diagram page 19
-9
22 -
Oil cooler
23 -
Belt pulley
For viscous fan
24 -
Fan wheel for viscous fan
25 -
Viscous fan coupling Note left-hand threadTightening torque only valid when using
3312 open end spanner. Tighten to 40 Nm (30 ft lb)Removing and installing page 19
-25
26 -
Bracket
For viscous fan
27 -
From bottom of radiator Coolant hose connection diagram page 19
-9
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