Radiator hose AUDI A4 1999 B5 / 1.G AHA ATQ Engines Cooling System Components Workshop Manual

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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19-4


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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19-7


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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19-9


Coolant hose connection diagram

1 -
Lower coolant hose
From radiator to engine
2 -
Cylinder head/cylinder block
3 -
Intake manifold
4 -
Coolant line From heat exchanger to engine block
5 -
Heater core
6 -
Coolant hose To heat exchanger
7 -
Rear coolant line
8 -
Expansion tank
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19-10


9 -
Oil cooler
10 -
Coolant line
From expansion tank to lower coolant pipe
11 -
Upper coolant hose
12 -
Radiator
13 -
Coolant pump
14 -
Lower coolant line
15 -
Connection For thermostat
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19-11

Cooling system, draining and refilling


Draining

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.

- Open coolant expansion tank cap.

- Remove noise insulation panel.
- Place VAG1306 drip tray underneath engine.

- With bumper removed, open coolant drain plug (arrow) on lower left of
radiator by turning it counterclockwise. If necessary, attach accessory
hose to connection.
-
With bumper installed, pull off retaining clamp for lower right radiator
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CAUTION!
Follow disposal regulations for coolant. hose (from radiator to engine) and disconnect radiator hose from
radiator.
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19-14

- Replace coolant drain plug O-ring and install
coolant drain plug into engine.

Tightening torque: 20 Nm (15 ft lb).

- Install lower right coolant hose and secure with
retaining clip.

- Secure coolant drain valve to radiator.

- Screw VAG1274/9 onto expansion tank and insert VAG1274/10 into
adapter.

- Loosen clamp on coolant hose on heater core and pull back hose until
bleeder hole in coolant hose (arrow) is no longer sealed by connection.
- Top off coolant until it flows out from bleeder hole in coolant hose.
- Push coolant hose onto connection and tighten.
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19-16

- Raise engine speed to approx. 2000 rpm for
approx. 5 minutes.

- Allow engine to idle until lower coolant hose on
radiator is hot.

- Check coolant level and top-off if necessary.
When engine is at normal operating
temperature, coolant level must be on MAX
mark. When engine is cold, coolant level must
be between MIN and MAX marks.

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.
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11/21/2002 htt
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pair&id=AUDI.B5.GE03.19.1