1. Cooling fan motor
2. Radiator
ENGINE COOLING 6B-3
THERMOSTAT
A wax pellet type thermostat is used in the coolant outlet passage
to control the flow of engine coolant, to provide fast engine warm
up and to regulate coolant temperatures.
A wax pellet element is hermetically contained in a metal case, and
expands when heated and contracts when cooled.
When the pellet is heated and expands, the metal case pushes
down the valve to open it.
As the pellet is cooled, the contraction allows the spring to close the
valve.
Thus, the valve remains closed while the coolant is cold, preventing
circulation of coolant through the radiator.
At this point, coolant is allowed to circulate only throughout the en-
gine to warm it quickly and evenly.
As the engine warms, the pellet expands and the thermostat valve
opens, permitting coolant to flow through the radiator.
In the top portion of the thermostat, an air bleed valve (1) is pro-
vided; this valve is for venting out the gas or air, if any, that is accu-
mulated in the circuit.
Thermostat functional spec. ± 2.8C (5.0F)
Temp. at which valve
begins to open88C (190F)
Temp. at which valve
become fully open100C (212F)
COOLING FAN
The cooling fan is driven by electric motor, and the motor is acti-
vated by ECM / PCM (engine coolant temp.). For its details, refer to
Section 6E.
WARNING:
Keep hands, tools, and clothing away from engine cooling
fan to help prevent personal injury. This fan is electric and
can come on whether or not the engine is running. The fan
can start automatically in response to the ECM / PCM (en-
gine coolant temp.) with the ignition switch in the “ON”
position.
