You bought a 1991 ford escort it doesnt have a heater thermostat you would like to know which way it goes in the housing?
spring side goes toward the intake, most thermostats have an arrow on them that points toward the radiator
the thermostat is located between the thermostat housing and the cylinder head. To locate the thermostat housing you can follow the upper radiator hose. The part connecting the upper radiator hose to the cylinder head/engine is the thermostat housing. To remove it to access the thermostat will require the use of a 10mm wrench and the draining of the engine coolant
To find the thermostat, first find the upper radiator hose going from the radiator to the engine. It's a big 3 inch hose. Where the hose connects to the engine is where the thermostat is at. It's called the water outlet housing. The housing contains the thermostat, 2 sensors and the hose going to the heater. Take this housing off and the thermostat is located inside of the housing. When replacing the thermostat make sure…