Yes, winter is on its way, and with it comes an entirely new set of problems. It may seem strange that you have overheating of motor vehicles in winter, but there are reasons for these problems.
During summer you have almost never used your heater in the car, which means the heater radiator inside the vehicle has probably run dry.
The first cold day of winter and on goes the heater. The water from the engine flows into the heater unit and takes about two litres of water out of the cooling system.
When you switch the heater off the water remains in the heater and the engine is short two litres, and this can result in the engine overheating.
The repair some of the time is as simple as topping up the radiator with water or anti-freeze.
Speaking of which, anti-freeze/summer coolant, is as necessary as fuel in your car and is not there to make the water in the cooling system look pretty.
Anti-freeze has other properties and also acts as a lubricant for the water pump.
It thus prevents premature water pump failure which would result in overheating, possible blown head gaskets and, in some instances, engine failure.
Yes, you read correctly, engine failure due to water-pump failure is not uncommon on vehicles that are designed with cambelt driven water pumps. When such a water pump fails, the cambelt inevitably breaks or teeth shear off, resulting, in most instances, in a rather expensive repair that could have been prevented by anti-freeze.
PREVENTATIVE MEASURE
With temperatures falling to below zero in some areas, anti-freeze can also prevent cylinder blocks and heads from cracking.
A relatively cheap preventative measure would be to have the cooling system flushed and a good anti-freeze put in.
It is also not unusual to find something as simple as a faulty radiator cap causing overheating problems.
Cars with viscous fans and temperature-controlled fan units can also give overheating problems.
Often it requires a replacement of the viscous unit on the fan or if the vehicle is fitted with an electric fan, the replacement of the thermoswitch can in many instances resolve the problem at a relatively low cost. On some of the modern or later-model cars the replacement of the entire fan unit is required and it can get expensive, but still not as costly as an engine repair.
Stay cool or warm this winter, never overheat.
The funny thing about cooling systems is the fact that when you repair or replace a component in one area, there is often another point in the system that inevitably leaks or ruptures. Take for example your radiator hoses. If one of them bursts because of plain wear and tear, replace all the hoses in the system, or all the main ones. This ensures that there are almost no weak points that can let go after the repair.
If the cooling system has been worked on, always check your water level for a few days after that. In some instances that require the bleeding of the system, it is not uncommon for there to be some air in the system. This will result in the water level in the radiator dropping.
You may have to top up the water. Ensure that you do so when the vehicle is cold and that you check both the water level in the expansion bottle and the radiator. - Star Motoring