Engine Overheating

A vehicle engine can be overheated at any weather or season. Chemical energy in the fuel becomes converted into thermal energy when fuel burns making the car run and if this process is not watched and controlled, the overheating might appear.

Engineers have been working on the creation of new engines which could tolerate higher temperatures making them out of metallic-ceramic alloys and trying to substitute as many parts as possible with exotic ceramic materials. This kind of engines is very expensive and is not used in usual vehicles. An average engine is designed to operate within 195-220 degrees F. A 50/50 mixture of water and ethylene glycol antifreeze in the cooling system will boil at 225 degrees F. If the mixture is moved up to maximum recommended 70% antifreeze and 30% water, the engine should be safe up to 276 degrees F.

A coolant does not always save the engine. Sometimes it is made with aluminum heads or some other parts which are sensitive to the temperatures higher than normal, so any time the temperature gets too high, the owner should watch out.

Engine overheating can ruin a car very quickly. High temperatures can damage and burn holes in the parts, ruin the rings, pistons or rod bearings, blow a head gasket. If the coolant starts boiling, old hoses and radiator might burst, pistons swell up and seize in their bores, exhaust valve stems stick or scuff in their guides.

An overheating can be caused by a number of reasons. The most common one is overworking the engine, especially in hot weather. Other reasons are closely connected to the cooling system, which fails to do its work in full. Here are the main reasons of the system failure:

•    A low coolant level;
•    A coolant leak;
•    Poor heat conductivity inside the engine caused by deposits in the water jackets;
•    Bad airflow through the radiator;
•    A slipping fan clutch;
•    A failure in the work of the electric cooling fan;
•    A broken lower radiator hose;
•    A loose or eroded water pump impeller;
•    Dragging brakes.

If the HOT warning light is on, the immediate measures have to be done without a delay. It takes time to cool off the engine, but it is cheaper to wait and save the vehicle, than to regret later, when the engine will blow up. The simplest action is to turn off the engine, let it cool down and then try starting it again.

A good idea would be to turn on the heater to maximum and switch the blower fan on, because it usually draws the heat off the engine. Sometimes it helps to stop, shift to Neutral and rev the engine at a fast idle speed. If after these actions the temperature of the engine is not going down, there is a bigger problem than simple overworking.

In this case the driver should pull over to a side, lift the hood carefully, because it will be hot too, and check all the details. First of all the amount of coolant should be checked. If it is low and there is no way to buy antifreeze, even simple water will work better than no coolant at all. However, as soon as possible it should be drained and replaced by a mixture of antifreeze and water. The driver should also check all the details: plugs, belts, fans. There might be too many insects or debris covering the radiator. If there is no obvious reason, the vehicle should be taken to a bodyshop and checked for leaks.

Careful work with the engine, regular maintenance, and close attention to the popping-up lights saves both the motor and the whole car.

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