My 40-year-old classic car overheated recently. The workshop which maintains the car checked the cooling system and discovered that the thermostat was rusted and had seized. So the mechanic suggested I remove the thermostat and not replace it, so this problem will not recur. Is this advisable? If so, what is the purpose of the thermostat and can I remove it from any car?

Before considering the worth of a thermostat, you should evaluate the cause of the corrosion around this device. Obviously, your car's cooling system was filled with plain water. The first thing to do is drain the entire cooling system and fill with water plus an appropriate proportion of coolant.

This is an important mix, as the coolant raises the boiling point and acts as an anti-corrosion agent. It also provides lubrication to the water pump, hence reducing wear.

The thermostat is a valve that regulates coolant flow from radiator to the cylinder head and engine block in order to maintain optimum operating temperature. It remains closed when the engine is cold to enable quicker warm-up and opens to allow the coolant from radiator to circulate through the engine.

In Singapore's warm climate, the thermostat will stay open most of the time. While it is usually not a problem if the car is driven mostly in the city, the lack of a thermostat could cause temperature issues when one is cruising for long periods on the highway.

The unregulated coolant flows at a rate that is too high for efficient heat transfer, resulting in higher-than-normal engine temperature.