Overheating can cause massive damage to a car engine. Keeping an eye on your car's cooling system and having it serviced regularly can help prevent such harm.

Problems commonly occur with two small but vital parts of the cooling system: the radiator cap and the thermostat.

Radiator Cap Problems

Problems with the radiator cap can cause your car to overheat. The radiator cap has a spring-loaded plunger which works to maintain pressurized conditions in the radiator. Increased atmospheric pressure raises the boiling point of fluids. The pressurized conditions in the radiator increase the point at which the coolant in your car boils. Delaying the point at which coolant boils helps to keep your engine cool.

As the coolant heats up once your car is running, the pressure in the radiator increases. As the pressure increases past what is optimum, the spring-loaded plunger in the radiator cap lifts and this allows coolant to flow into the overflow reservoir, so lowering the radiator pressure. As the pressure decreases, coolant flows back from the reservoir tank into the radiator.

If the plunger becomes stuck, this can block coolant overflowing into the tank. The radiator and cooling system may then develop leaks to relieve the pressure that builds up.

Additionally, if the rubber seal on the radiator cap becomes worn, the coolant can leak out the top of the radiator.

Leaking coolant can cause the car to overheat because it means the correctly pressurised conditions aren't being maintained; the coolant boils more readily and so does not function effectively to cool the engine. Low levels of coolant also might mean that not enough coolant is flowing throughout the system to cool the car's running temperature.

Thermostat Problems

Your car needs to be warm for it to run at its optimum. The thermostat measures the temperature of the coolant and either opens or closes accordingly. When your car is cold, the thermostat remains in the closed position preventing the coolant from flowing throughout the cooling system, and this allows the engine to warm up more quickly. Once an optimum temperature is reached, the thermostat opens, allowing the coolant to flow.

Sometimes the thermostat gets stuck in either the open or closed position. If it sticks in the open position, the engine takes longer to warm up as the coolant isn't correctly being held back until the engine is warm.

If the thermostat gets stuck in the closed position, the coolant is blocked from flowing, and your engine will soon overheat.

Sometimes the thermostat gets stuck in a partially open position, and this can cause both problems. It may be open enough to prevent your engine warming as quickly as it should, and it may also not allow enough coolant flow-through to keep the engine cool after it has been running for a while.

It is important to prevent your car overheating and possibly causing damage to your engine. If you have any doubts about your cooling system, don't hesitate to visit an auto mechanic like Treg Smiths Auto's Pty Ltd to have it checked out. You might avoid massive problems in the long run.