Cooling Syste and Installing 1.8 T

19-1

Cooling system components, removing and installing

WARNING!

When doing any repair work, especially in the engine compartment, due to the cramped conditions, pay attention to the following:

Route all sorts of pipes (e.g. for fuel, hydraulics, evaporative emissions system, coolant, refrigerant, brake fluid and vacuum pipes and hoses) and electrical wiring so that the original positions are restored.

Make sure sufficient clearance to all moving or hot components.

Note:

When the engine is warm the cooling system is under pressure. If necessary release pressure before commencing repair work.

Hoses are secured with spring-type clips. In cases of repair only use spring-type clips.

Assembly tool VAS 5024 or hose clip pliers V.A.G 1921 are recommended for installing spring-type clips.

When installing coolant hoses route stress-free, so that they do not come into contact with other components (observe markings on coolant connection and hose).

Página 1 de 42Cooling system components, removing and installing

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19-2

Perform cooling system leakage test with cooling system tester V.A.G 1274 and adapters V.A.G 1274/8 and V.A.G 1274/9.

Parts of cooling system body side Page 19-3 .

Parts of cooling system engine side Page 19-6 .

Coolant hose connection diagram Page 19-12 .

Draining and filling with coolant Page 19-18 .

Coolant mixture ratios Page 19-18 , draining and filling with coolant.



19-3

Cooling system components (body side)

1 - Radiator

Removing and installing

Page 19-25

After replacing replace entire coolant

2 - O-ring

Replace if damaged

3 - Upper coolant hose

Secured to radiator with retaining clip

Check securely seated

Coolant hose connection diagram Page 19-12

4 - Air ducting



5 - 10 Nm

6 - Additional fan

Only vehicles with optional equipment



19-4

7 - Fan ring

8 - Retaining clip

Check seated securely

9 - Connector

10 - Coolant fan

11 - Bracket

For radiator fan connector

12 - Lower coolant hose




13 - O-ring

Replace



19-5

14 - Coolant Fan Control (FC) thermo switch -F18-, 35 Nm

For electric fan

Switching temperatures:

Stage 1 on: 92 to 97 C; off: 84 to 91

C

Stage 2 on: 99 to 105 C; off: 91 to 98 C

15 - Bracket

For radiator

Note installed position

16 - 15 Nm



19-6

Cooling system components (engine side)

1 - 15 Nm

2 - Toothed belt

Mark direction of rotation before removing

Check for wear

Do not kink

Removing, installing and tensioning

Page 15-6

3 - Coolant pump

Check for ease of movement

If damaged or leaking replace complete


Page 19-28



4 - O-ring

Replace



19-7

5 - Coolant thermostat

Checking: heat-up thermostat in water

Opening commences approx. 87

C

Ends approx. 102 C

Opening lift min. 7 mm

6 - O-ring

Replace

7 - Connection

8 - To heat exchanger


9 - O-ring

Replace

10 - Connector

4 pin



19-8

Repair Manual , 1.8 Liter 4-Cyl. 5V Turbo Fuel Injection & Ignition, Repair Group 01 DTC memory; DTC memory, checking and erasing

11 -

Engine Coolant Temperature (ECT) sensor -G62-

With Engine coolant temperature (ECT) gauge sensor -G2-

For engine control module

If necessary release pressure in cooling system before removing

Checking:

12 - Retaining clip

Check seated securely













19-9

15 - Oil cooler


Page 17-11 , item 22

16 - From heat exchanger


17 - Lower coolant pipe


18 - 10 Nm

19 - Cap

Check with cooling system tester V.A.G 1274 and adapter V.A.G 1274/9

Test pressure 1.4 to 1.6 bar



20 - Seal

Replace if damaged

21 - 10 Nm



19-10

22 - Expansion tank

Carry out leak test of cooling system with cooling system tester V.A.G 1274 and adapter V.A.G1274/8

23 -

To turbocharger


24 - 15 Nm

25 - To upper coolant hose

Only engine code AWP with automatic transmission


26 - After-Run coolant pump -V51-

Only engine code AWP



with automatic transmission


Checking Page

19-34



19-11

27 -

From turbocharger

Only engine code AWP with automatic transmission




19-12

Coolant hose connection diagram

Only vehicles with engine code AWD

Vehicles with engine code AWP (manual transmission), AWW (manual and automatic transmission) Page 19-14

Vehicles with engine code AWP (automatic transmission) Page 19-16

1 - Radiator

2 - Oil cooler

3 - Coolant thermostat housing

4 -

Cylinder head/cylinder block

5 - Expansion tank

6 - Turbocharger



19-13

7 - Heating system heat exchanger

8 - Connection

9 -

Transmission oil cooler

Only with automatic transmission


11 - Intake manifold

12 - Drain plug



19-14

Vehicles with engine code AWP (manual transmission), AWW (manual and automatic transmission)

1 - Expansion tank

2 - Turbocharger

3 - Intake manifold

4 -


5 - Connection



8 -


Only engine code AWW with automatic transmission


10 - Drain plug

11 - Radiator

12 - Lower coolant



hose



19-15

13 - Oil cooler


15 - Coolant pump

16 - Coolant pipe



19-16

Vehicles with engine code AWP (automatic transmission)

1 - Expansion tank

2 - Turbocharger

3 - Intake manifold

4 -


5 - Coolant pipe

6 - Connection


8 -


Only with automatic transmission


10 - Oil cooler




19-17

12 - Radiator


14 - After-Run coolant pump -V51-


16 - Coolant pump



19-18

Cooling system, draining and filling

Special tools and equipment

T10007 Refractometer

V.A.G 1306 Drip tray

VAS 5024 Assembly tool for spring-type clamps



19-19

Draining

WARNING!

Steam can be released when removing the cap from the expansion tank. Cover cap with a cloth and open carefully.

- Open cap on coolant expansion tank.

- Remove insulation tray:

Repair Manual , Body Exterior, Repair Group 50; Body-Front; Sound insulation (gas engine) - assembly overview.

- To drain coolant from radiator remove drain plug -arrow-.



19-20

Note:

Observe disposal regulations!

Filling

Note:

- To drain coolant from engine also remove coolant hose from oil cooler -arrow-.

Only use coolant additive G 12 in accordance with TL VW 774 D. Identification: colored red

On no account must G 12 be mixed with other coolant additives!

If the fluid in expansion tank is brown, G 12 has been mixed with other coolant. In this case the coolant must be changed.

G 12 and coolant additives marked "In accordance with TL VW 774 D" prevent frost and corrosion damage, scaling and also raise boiling point of coolant. For this reason the system must be filled all year round with frost and corrosion protection additives.

Because of its high boiling point, the coolant improves engine reliability under heavy loads, particularly in countries with tropical climates.



19-21

Protection against frost must be assured to about -25 C (in arctic climatic countries to about -35 C).

The coolant concentration must not be reduby adding water even in warmer seasons anwarmer countries. The anti-freeze ratio musat least 40 %.

If for climatic reasons a greater frost protectis required, the amount of G 12 can be increased, but only up to 60 % (frost protecto about -40 C), as otherwise frost protectis reduced again and cooling effectiveness also reduced.

Recommended mixture ratios:

1) The quantity of coolant can vary depending uthe vehicle equipment.

The T10007 refractometer is recommendeddetermining frost protection density.

If radiator, heat exchanger, cylinder head orcylinder head gasket is replaced, do not reuold coolant.

Frost protection to

Anti-freeze amount

G 121)

Wat

-25 C

-35 C

40 %

50 %

2.0 ltr.

2.5 ltr.

3.0

2.5



19-22

- Screw drain plug into radiator.

- Push coolant hose onto oil cooler connection and secure with a spring-type clamp.



19-23

Vehicles of model year 2001

- Fill with coolant up to max. mark on expansion tank.


- Slowly fill expansion tank to upper marking of shaded field with coolant.



19-24

Continuation for all vehicles

- Install expansion tank cap.

- Switch off heater and air conditioner.

- Start engine and maintain an engine speed of about 2000 RPM for approx. 3 minutes.

- Run engine until coolant fan starts.

WARNING!

Steam can be released when removing the cap from the expansion tank. Cover cap with a cloth and open carefully.

- Check coolant level and top-up if necessary.


When engine is at normal operating temperature, coolant level must be on the max. mark. When engine is cold, between min. and max. marks.


When engine is at normal operating temperature, coolant level must be at upper marking of shaded field.

When engine is cold, coolant level should be at approximately middle of shaded field.



19-25

Radiator, removing and installing




V.A.G 1331 Torque wrench (5 to 50 Nm)




19-26

Removing

- Drain coolant Page 19-18 .

- Remove front bumper:

Repair Manual , Body Exterior, Repair Group 63; Front bumper, removing and installing front bumper

- Remove coolant hoses from radiator.

- Disconnect connector of thermo-switch.

- Bring lock carrier into service position:

Repair Manual , Body Exterior, Repair Group 50; Body, front; Lock carrier service position

- Remove radiator securing bolts and take radiator with fan out downward.

Note:

Vehicles with air conditioner:

- Observe additional information and removal work Page 19-27 .

Installing

Installation is carried out in the reverse order. Note the following:

Filling with new coolant Page 19-18 .



19-27

Additional information and removal work on vehicles with air conditioner

CAUTION!

The air conditioner refrigerant circuit must not be opened.

Note:

To prevent damage to condenser also to the refrigerant lines/hoses, make sure that the lines and hoses are not stretched, kinked or bent.

- Remove retaining clamp(s) from refrigerant lines.

- Remove condenser from radiator and secure to lock carrier.



19-28

Coolant pump, removing and installing








19-29

Note:

Always replace seals and gaskets.

The lower part of the toothed belt guard neenot be removed.

The toothed belt should be left in position onthe crankshaft sprocket.

Cover toothed belt with a cloth to protect it fcoolant before removing coolant pump.

Removing

- Drain coolant Page 19-18 .

- Remove ribbed belt Page 13-10 .

- Remove upper and center parts of toothed bguard Page 15-6 , Removing, installing antensioning toothed belt.

- Take toothed belt off coolant pump toothed bsprocket Page 15-6 , Removing, installingtensioning toothed belt.

- Unscrew coolant pump securing bolts -1- anremove coolant pump -2-.



19-30

Installing


- Moisten new O ring with coolant.

- Insert coolant pump into cylinder block and tighten securing bolts. Tightening torque: 15 Nm

Note:

The coolant pump plug faces downward.

- Install toothed belt and adjusting timing Page 15-6 .

- Install ribbed belt Page 13-10 .




19-31

Thermostat, removing and installing








19-32

Removing

Note:

Always replace seals and gaskets.

- Drain coolant Page 19-18

Installing


- Pull coolant hose off connecting flange -3-.

- Unbolt securing bolts -4- of connecting flange -3- and remove connecting flange -3- with thermostat -1-.

- Moisten new O ring -2- with coolant.

- Insert thermostat -1- into connecting flange -3- and turn 1/4 turn (90 ) to right.

- Install connecting flange -3- with thermostat -1- into engine block.



19-33

Note:

The brace on the thermostat must be almost vertical.


- Tighten securing bolts -4-. Tightening torque: 15 Nm



19-34

After-run coolant pump, checking


VAG 1527B voltage tester

V.A.G 1594 A Auxiliary test set

Wiring diagram



19-35

Check conditions

Test sequence

All fuses must be OK.

- Pull 2-pin connector off After-Run coolant pump -V51- -arrow- .



19-36

If the after-run coolant pump does not run:

If the After-Run coolant pump -V51- runs:

- Connect contacts of After-Run coolant pump -V51- to battery using aux. cables from V.A.G 1594. After-run coolant pump must run.

- Replace After-Run coolant pump -V51-.

- Switch ignition off and on again.

Note:

This check must be performed within 5 minutes after switching ignition off.

If the LED does not light up:

Electrical Wiring Diagrams, Troubleshooting & Component Locations

- Connect VAG 1527B voltage tester to disconnected connector for after-run coolant pump (V51) with auxiliary cable from V.A.G 1594 A LED must light up.

- Locate and repair open circuit using wiring diagram:



Cooling Syste and Installing 1.8 T

Documents

coolant page

coolant connection

parts of cooling system

cooling system tester

parts of cooling system

cooling system leakage

entire coolant

connector10 coolant