You might need a new heating coil.
60 to 66 LBS. Key on engine off. Can be 50 LBS. running.
Need to know your engine size in order to anwer your thermostat problems.
On my 95 pickup with 4 cylinder engine, the thermostat is located where the lower radiator hose enters the engine block. Hope this helps.
The spring on the thermostat goes down towards the engine.
Just to the side of the thermostat housing.
It is under the housing that the upper radiator hose hooks to on the engine.
follow lower radiator hose back to 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.
The thermostat is located on the passenger side of the engine. It you follow the top radiator hose to the engine, it is clamped to a housing. The thermostat is inside this housing. The housing is bolted to the engine block. There is a gasket to seal between the two parts. If you remove the housing, the thermostat just drops out.
Look in the removable housing at the engine end of the upper radiator hose
On top of the engine attached to the top radiator hose. Two bolts holding it in, take them off and the thermostat is right there.
Look in a removable housing at the engine end of the upper radiator hose