Thermostat - removal, testing and refitting

Cooling, heating and air conditioning systems / Thermostat - removal, testing and refitting

1.05 and 1.3 litre engines Removal
1 The thermostat is located in the outlet housing on the left-hand (rear) end of the cylinder head. To remove it, first drain the cooling system.

2 Unscrew the bolts and remove the thermostat cover (see illustrations). Place the cover with top hose still attached to one side.

5.2a Unscrew socket-head bolts . . .

5.2b . . . and remove thermostat cover

3 Remove the sealing ring (see illustration).

5.3 Removing thermostat sealing ring

4 Extract the thermostat from the outlet housing.

Testing
5 To test the thermostat, suspend it with a piece of string in a container of water.

Gradually heat the water and note the temperature at which the thermostat starts to open. Continue heating the water to the specified fully open temperature then check that the thermostat has opened by at least the minimum specified amount. Remove the thermostat from the water and check that it is fully closed when cold.

6 Renew the thermostat if it fails to operate correctly.

7 Clean the thermostat seating and the mating faces of the outlet housing and cover.

Refitting
8 Refitting is a reversal of removal. Fit a new sealing ring and tighten the cover bolts to the specified torque. The breather hole in the thermostat should face upwards.

9 On completion, refill the cooling system.

1.6 and 1.8 litre engines Removal
10 The thermostat is located in the bottom of the coolant pump behind the inlet elbow. To remove it, first drain the cooling system.

11 Unbolt the inlet elbow from the coolant pump and remove the seal and thermostat (see illustrations).

5.11a Undo the retaining bolts . . .

5.11b . . . withdraw thermostat elbow . . .

5.11c . . . then extract thermostat and seal

12 Clean the coolant pump and elbow of any scale or corrosion.

Testing
13 To test the thermostat, proceed as described in paragraphs 5, 6 and 7.

Refitting
14 Refitting is a reversal of removal procedure. Always fit a new seal.

15 On completion, refill the cooling system.