Operation

OPERATION

The thermostat's primary purpose is to maintain engine temperature in a range that will provide satisfactory engine performance and emission levels under all expected driving conditions.

The thermostat is unique because the center does not open and close like a conventional thermostat; it works like a sliding sleeve. The outside sleeve moves, directing coolant flow through the engine block or through the bypass passages back to the water pump. During warm-up below 85°C (185°F), the thermostat is seated in the retracted position. This will allow the coolant to flow into the bypass passage, and back to the water pump. At 85°C (185°F) the thermostat begins to open, allowing coolant to flow through both the bypass and the radiator. At 97°C (207°F) the thermostat will fully open, blocking the path to the bypass, allowing all coolant to flow through the radiator.