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Why Do Cars Overheat in the Winter?

Why do Cars Overheat in the Winter?

Most cars come with internal combustion engines and can overheat in extremely cold temperatures. Engines produce heat from two things:  friction and combustion. Friction, from the internal components moving at a very fast rate against each other and combustion, from fuel and air compressing to produce energy.

These temperatures can reach extremes beyond what the engine can handle to run properly. Cooling systems are part of an engine’s operating system to regulate the temperature, even in exceptionally cold temperatures.

Why Does Overheating Occur?

Overheating occurs in winter due to a fault that occurs in a vehicle’s cooling system. Most common faults are coolant leaks or a blocked thermostat.

Coolant passes through the engine’s coolant passages, as it does the heat that is produced by friction and combustion, in the engine and is transferred into the coolant. The coolant then travels to the radiator where the heat is dissipated by air that is passing through the radiator.

When a leak occurs and the cooling system becomes very low, the coolant no longer passes through the engine’s coolant passages. Instead, air passes through which will not transfer the heat to the radiator, that the engine creates, thus, the engine accumulates heat and eventually overheats.

A jammed thermostat will stop the flow of coolant, as well, which will also result in overheating.

What Can You Do to Prevent Overheating?

“An ounce of prevention is worth a pound of cure.” Maintenance is the key to any vehicle’s cooling system. Have your vehicle’s cooling system inspected for potential leaks, check hoses, thermostat, coolant condition, and level.

In between professional inspections check the coolant reservoir level, on an occasional morning, when the car is cool to make sure the level is full.

What Can You Do if Your Car Overheats?

If while driving your vehicle you have the unfortunate circumstance of the temperature rising quickly or the vehicle begins to overheat, safely pull over to the side of the road and turn the engine off. This is very important as most engines are made of aluminum when overheated it is prone to warping or cracking. This can cause significant damage to the engine itself and can result in a cylinder head replacement or engine replacement.

It is critical to turn the engine off as soon as possible and if you are able, open the hood to allow heat to dissipate quicker. Be sure to exercise extreme caution, even in freezing temperatures the hood can get very hot. Most importantly, do not attempt to remove the radiator cap.

Many drivers think overheating only happens in the summer when temperatures are very hot and the cooling system is under the most stress. However, overheating can occur just as often in the winter as well. To avoid overheating no matter the season, check and maintain your cooling system all year long.