Have you check to see if the radiator is clogged with dirt and debris try pressure washing the radiator and make sure the fan is working like it should. If you clean the fins and it still runs hot you might check to see if the temp guage is reading correct.
Four cylinder, it is where the upper radiator hose attaches. Six cylinder, it is where the lower radiator hose attaches.
To replace the thermostat on a 91 Cavalier you need to drain the radiator. Remove the top radiator hose and water inlet. Remove the thermostat from under the inlet. Install the new thermostat and reinstall the inlet and hose. Fill the radiator with fresh antifreeze.
The thermostat is under the housing where the upper radiator hose attaches to the engine.The thermostat is under the housing where the upper radiator hose attaches to the engine.
Follow the upper radiator hose from the radiator towards the engine. The upper radiator hose is connected to the thermostat housing on the engine side.
On the 4 cylinder Saturn, follow the top radiator hose back to the engine. Note that there is a housing that is bolted to the engine to which the radiator hose is connected. Remove the radiator hose first, then remove the housing. On the 4 cylinder Saturn's, the thermostat is a part of that housing.
4 cylinder : it is under the housing that the upper radiator hose hooks to.6 cylinder : It is under the housing that the lower radiator hose hooks to.4 cylinder : it is under the housing that the upper radiator hose hooks to.6 cylinder : It is under the housing that the lower radiator hose hooks to.
The best indication of a bad thermostat is when the radiator fluid (Antifreeze) boils over from the reserve tank, not the radiator. This is caused by the thermostat not opening at its preset temperature and all the extra antifreeze is pumped directly to the reserve tank. You will also have loss of power and the vehicle will likely stop running soon after the antifreeze boils over.
Cleans antifreeze and dirt out of the radiator
Thermostat messed up, Oil needs to be changed, no antifreeze in the radiator, radiator fan is not working properly
Four cylinder, it is where the upper radiator hose attaches to the engine. Six cylinder, it is where the lower radiator hose attaches to the engine.
Drain the radiator into a container. Remove the upper radiator hose at the engine end. there is 2 bolts in the housing that hold the thermostat. Remove them and the thermostat and clean both surfaces. Install the new thermostat and housing. Install the upper hose and top off the radiator with a 50/50 mixture of antifreeze and water.
Drain the radiator into a container. Remove the upper radiator hose at the engine and remove the 2 bolts in the thermostat housing. Remove the thermostat and clean both surfaces. Install the new thermostat and upper hose. Top off the antifreeze.