Keep Your Cool: Essential Tips for Maintaining Your Vehicle’s Cooling System
We are entering the time of year where our region receives some very warm temperatures and with that comes a strain on our vehicles cooling system.
For those not familiar, the way our cooling system works is that the car engine generates a lot of heat from the combustion cycle, and this heat is transferred to the cooling system via water jackets that surround each cylinder.
The coolant moves through these water jackets via the water pump, which pulls the cooled water from the radiator and pushes it through the engine, returning to the radiator.
When you’re driving, the air passing through the radiator, cools the coolant. The coolant is then returned to the engine.
Therefore, on days where the temperature is extreme, the hot air can cause overheating on a cooling system that is not operating effectively. Within the cooling system there is a thermostat, and the thermostat is there to maintain a minimum operating temperature. It does this by restricting the flow of the coolant, opening and closing until the temperature of the coolant reaches a set target.
Cooling system pressure is a contributing factor to be considered in a cooling system as it is a by-product of the heat created. As the water reaches boiling point of 100 degrees Celsius, it expands, and in some modern vehicles the thermostat will not fully open until 92 degrees Celsius.
This could send the engines normal operating temperature over 100 degrees Celsius. The radiator cap will delay the temperature of when that water inside the cooling system boils. For example a 15 PSI (pounds per square inch) radiator cap will result in the coolant not boiling until it reaches 124 degrees Celsius. Every PSI above 7PSI, delays boiling by three degrees Celsius.
One of the common reasons why a cooling system fails is a failed hose which is where the hose can become brittle, cracked, or split due to extreme temperatures over time. Another common reason is a failed radiator cap where the seal is likely to swell over time due to the chemicals that are utilised in coolants. Additionally, a failed thermostat can be the cause due to repetitive opening and closing over time.
Larger failures can be caused by a failing radiator which leaks or has started to degenerate which means it is no longer effective. A failed water pump could also be the cause thanks to a bearing wearing out, causing a water leak at the bearing seal.
The cooling system can become ineffective if rust scale builds up within the radiator. This rust scale is caused by a breakdown of the chemicals in the coolant. The different metals within the engine can cause the properties of the coolant to deteriorate, and the coolant will lose effectiveness in keeping the system clean and healthy. When this happens deposits of rust and scale will move throughout the system thanks to the water pump, and will block the flow to the radiator.
If you experience a cooling system failure, some actions you can take are:
- If the system is leaking and you can see a drip, top up your system with plain water until you can reach an automotive workshop for diagnosis and repair.
- If the system is leaking significantly, you may need to be towed to an automotive workshop for diagnosis and repair.
Please remember never to take your radiator cap off while the system is hot and under pressure. If you are unsure if it is hot and under pressure, use a rag to squeeze the top radiator hose. If you can squeeze the hose easily, then the pressure in the system is very low or non-existent. Taking the radiator cap off while the system is under pressure, will cause serious burns.
If you’re unsure whether there is pressure or not, be cautious and don’t proceed, rather, seek help.
Regular maintenance checks of your cooling system should be completed in conjunction with vehicle servicing, in line with the manufactures recommendations. Ensuring this step is completed as part of a comprehensive service will ensure failures are kept to a minimum.
