Removal and installation and checking the thermostat (Opel Kadett D)

When the engine temperature rises, the thermostat opens a large cooling circuit. If it fails, the engine overheats or does not reach operating temperature. The coolant temperature gauge indicates engine overheating, with a completely cold radiator. The opposite occurs with a constantly open large circuit. Due to a faulty thermostat, the engine, especially in winter, will not reach operating temperature.

ONS engines 1.6-/1.8-l

Removal

Remove the air filter, see paragraph 4.44.

Unscrew the expansion tank cap.



Place a container under the radiator hose. Unscrew the thermostat cover. Collect the coolant.



Remove and check the thermostat.

Installation

Install the thermostat and housing with a new seal.

Fill with coolant and screw on the expansion tank cap.

Install the air filter, see paragraph 4.44.

Diesel engine

Removal

Unscrew the expansion tank cap.



Place a container under the pipe.

Unscrew the thermostat cover. Drain the coolant.



Remove and check the thermostat.

Installation

Install the thermostat and cover with a new seal.

Fill with coolant, bleed air from the system and screw on the expansion tank cap.

ONS engines 1.2-/1.3-l

Removal

Remove the upper coolant hose from the thermostat housing, remove the radiator, drain and collect the leaking coolant.





Remove the timing belt guard. Move the cover aside.



Remove the thermostat and check.

Installation

Install the thermostat with a new seal. When doing this, pay attention to the recess in the cylinder head (arrow).

Screw on the thermostat housing. Install the timing belt guard and upper radiator hose.

Fill with coolant and release air.

OHV engine

Removal

Drain and collect the coolant, see p. 3.2.

Thermostat (temperature controller) is located in the upper neck of the coolant pump.

The coolant hose is leaking from the branch pipe.



Remove the tension spring from the round groove using a screwdriver.



Remove the thermostat.

Installation

Install the thermostat with a new rubber gasket and secure with the tension spring.

Note: The arrow on the partition points upward.

Secure the coolant hose.

Fill with coolant.

Examination

To check, the thermostat should be heated in a water bath and it should be observed whether the regulator opens completely. Initial regulator opening moment: 91°C.

Full opening: 103°C.

Thermostat marking: 91°C/195°F.