Cavalier 1.6 1988 - william s
Does anyone know where the thermostat is situated
Cavalier 1.6 1988 - geoff C
On any car it is likely to be at the engine end of the top hose to the radiator. On this engine I am fairly certain that you will find the hose is connected to an aluminium housing with three bolts. This is the thermostat cover.

(Careful - they are small bolts and it is easy to break them if the threads have corroded. Douse them in penetrating oil)
Cavalier 1.6 1988 - Dynamic Dave
Geoff C is correct. Aluminium housing with three bolts. Standing in front of the car, follow the short hose from the top of the left hand side of the radiator to the aluminium housing.
Cavalier 1.6 1988 - Andrew Moorey (Tune-Up)
On some models you will have to go a bit deeper than this as the thermostat is located in the head under the rear cambelt cover. (thanks Vauxhall!) If you have this installation it is quite a job and you may as well replace the cambelt and tensioner at the same time. It is possible to get round it by just dropping the belt and cam sprocket off and bending the rear belt cover out of the way but I wouldnt advise it.

Happiness is a T70 at full chat!
Cavalier 1.6 1988 - Dynamic Dave
I stand corrected. Andrew M is in fact correct. It's only the 1.8 and 2.0 litre engines that have the thermostat where Geoff C and I earlier suggested. It can be changed with the cambelt left in situ - I did one on my old 1.3 litre Astra - but it can be damn awkward.

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