The thermostat has two outlets. One directs coolant to the radiator when the engine is at operating
temperature. The other directs coolant to the water pump until the engine reaches operating temperature.
The thermostat begins to open at 88 °C (190 °F) and is fully open at 96 °C (205 °F).
When engine coolant is below the 88 °C (190 °F) the thermostat is closed, blocking flow to the radiator.
Coolant is forced to flow through a bypass port back to the water pump.
When coolant temperature reaches the nominal opening temperature (88 °C [190 °F]) the thermostat
opens allowing some coolant to flow to the radiator. When coolant temperature exceeds 96 °C (205 °F),
the lower seat blocks the bypass port directing full coolant flow to the radiator.
