Recommended replacement interval for the part category Thermostat : 50000 km

Important!

This replacement procedure can be used for:
VAUXHALL Astra Mk IV (G) CC (T98) 1.6 16V (F08, F48), VAUXHALL Astra Mk IV (G) CC (T98) 1.4 16V (F08, F48) … View more

The steps may slightly vary depending on the car design.

This video shows the replacement procedure of a similar car part on another vehicle

Alternative products

Thermostat

Replacement: engine thermostat – VAUXHALL ASTRA Mk IV (G) Hatchback. Tools you need:

                      All-purpose cleaning spray
                    
                      Torque wrench
                    
                      Drive socket # E8 
                    
                      Torx bit T20
                    
                      Torx bit T30
                    
                      Ratchet wrench
                    
                      Clic-R collar pliers
                    
                      Seal scraper
                    
                      Flat Screwdriver
                    
                      Funnel
                    
                      Fluid container
                    
                      Microfibre towel
                    
                      Fender cover

Buy tools

Replacement: engine thermostat – VAUXHALL ASTRA Mk IV (G) Hatchback. AUTODOC recommends:

Check the condition of the coolant every time you replace the thermostat. Change the coolant if necessary.
Please note: all work on the car – VAUXHALL ASTRA Mk IV (G) Hatchback – should be done with the engine switched off.

Carry out replacement in the following order:

Step 1

Open the bonnet.

Step 2

Use a fender protection cover to prevent damaging paintwork and plastic parts of the car.

Step 3

Unscrew the fasteners of the air distribution housing assembly. Use Torx T20.
Step 4

Remove the air distribution housing assembly.
Step 5

Unscrew the engine cover fastener. Use Torx T30. Use a ratchet wrench.
Step 6

Unscrew the oil filler plug.
Step 7

Remove the oil filler cap.

Step 8

Cover the oil filler opening with a microfibre towel to prevent dirt and foreign objects from getting into the system.
Step 9

Remove the engine cover.

AUTODOC recommends:
Replacement: engine thermostat – VAUXHALL ASTRA Mk IV (G) Hatchback. Do not use excessive force when removing the part as this may damage it.
Step 10

Remove the microfibre towel from the oil filler opening.
Step 11

Install the oil filler cap.
Step 12

Unscrew the coolant reservoir cap.
Step 13

Lift the car using a jack or place it over an inspection pit.

Step 14

Clean the coolant drain plug. Use all-purpose cleaning spray.
Step 15

Prepare a container for fluids.
Step 16

Open the coolant drain tap. Use a flat screwdriver.
Step 17

Drain the coolant from the engine.

Replacement: engine thermostat – VAUXHALL ASTRA Mk IV (G) Hatchback. Tip from AUTODOC experts:
Caution! The coolant can be very hot.Wear gloves to prevent contact with hot liquid.All work should be done with the engine stopped.
Step 18

Wait until the coolant has completely flowed out of the drain hole.

Step 19

Close the coolant drain tap. Use a flat screwdriver.
Step 20

Lower the car.

Step 21

Loosen the coolant hose clamp. Use clic-R collar pliers.
Step 22

Detach the coolant hose. Use a flat screwdriver.

Replacement: engine thermostat – VAUXHALL ASTRA Mk IV (G) Hatchback. Tip from AUTODOC:
Caution! Coolant may leak out of the coolant lines and thermostat housing.
Step 23

Loosen the coolant hose clamp. Use clic-R collar pliers.
Step 24

Detach the coolant hose.

Replacement: engine thermostat – VAUXHALL ASTRA Mk IV (G) Hatchback. AUTODOC recommends:
Caution! Coolant may leak out of the coolant lines and thermostat housing.
Step 25

Cover the open end of the coolant hose with a microfibre cloth to prevent dirt and foreign objects from entering the system.
Step 26

Unscrew the thermostat housing fasteners. Use a drive socket #Е8. Use a ratchet wrench.
Step 27

Remove the thermostat housing.
Step 28

Remove the rubber strip.
Step 29

Cover the mounting seat of the thermostat housing with a microfibre cloth to prevent dirt and foreign objects from entering the system.
Step 30

Clean the mounting seats of the thermostat housing. Use a seal scraper. Use all-purpose cleaning spray.
Step 31

Remove the microfibre cloth from the mounting seat of the thermostat housing.
Step 32

Install the rubber strip.
Step 33

Install a new thermostat housing.
Step 34

Screw in the thermostat housing fasteners. Use a drive socket #Е8. Use a ratchet wrench.
Step 35

Tighten the thermostat housing fasteners. Use a drive socket #Е8. Use a torque wrench. Tighten it to 7 nm torque.
Step 36

Clean the thermostat housing. Use all-purpose cleaning spray.
Step 37

Remove the microfibre cloth from the coolant hose.
Step 38

Attach the coolant hose.
Step 39

Secure the coolant hose clamp. Use clic-R collar pliers.
Step 40

Attach the coolant hose.
Step 41

Secure the coolant hose clamp. Use clic-R collar pliers.
Step 42

Remove the coolant reservoir cap. Insert the funnel.
Step 43

Pour coolant in the coolant reservoir.

Replacement: engine thermostat – VAUXHALL ASTRA Mk IV (G) Hatchback. Tip from AUTODOC experts:
Only use the coolant recommended by the manufacturer.The coolant level should be at the MAX mark.Wait until the air goes out of the system.
Step 44

Run the engine for a few minutes. This should be done in order to remove residual air from the cooling system and to check if the components are operating correctly.

Step 45

Check the coolant level. If necessary, top up to the required level.
Step 46

Install the coolant reservoir cap.

Step 47

Screw on the coolant reservoir cap.
Step 48

Remove the oil filler cap.
Step 49

Cover the oil filler opening with a microfibre towel to prevent dirt and foreign objects from getting into the system.
Step 50

Install the engine cover and secure it.

AUTODOC recommends:
Caution! Do not use excessive force during installation. This may damage the fasteners of the car. VAUXHALL ASTRA Mk IV (G) Hatchback
Step 51

Remove the microfibre towel from the oil filler opening.
Step 52

Install the oil filler cap.
Step 53

Screw in the engine cover fasteners. Use Torx T30. Use a ratchet wrench.
Step 54

Tighten the oil filler cap.

Step 55

Reinstall the air distribution housing assembly.

Replacement: engine thermostat – VAUXHALL ASTRA Mk IV (G) Hatchback. Tip:
When installing, do not use excessive force to avoid damage to the part.
Step 56

Screw in the fasteners of the air distribution housing assembly. Use Torx T20.

Step 57

Remove the fender protection cover.

Step 58

Close the hood.

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