Tips for cooling system maintenance


Up to 70% of the energy burnt from petrol in a car engine is converted to heat. A car engine has a cooling system for two main functions. Firstly, to help reduce the heat the engine produces to allow the it to run at an optimal temperature, which is still fairly hot. Secondly, to allow the car to heat up quickly, when it is started, as engine components tend to wear quickly when running at temperatures which are too cold.

The cooling system of most new cars are composed of the radiator with a fan, a water pump, thermostat and sensors, as well as some fluids. These are the components that work together to maintain the engine’s temperature.

Maintaing your car’s cooling system will maximise efficiency and prolong the life of your cooling system and vehicle. It isn’t that hard, here are our tips.

  1. Replace coolant at the intervals recommended by the manufacturer, regardless of the condition of the coolant. You cannot gauge the effectiveness of coolant based on appearance.
  2. Use only products recommended by the manufacturer of your car. If this is not possible use one which meets Australian Standard AS/NZ 2108.1.1997 (Type A or Type B) at the very least.
  3. Don’t forget that coolant is also diverted to the heating system of a car and turn on the heater when draining, flushing or filling a system to ensure all coolant is affected/drained.
  4. If possible when replacing old coolant, try to flush the cooling system with a quality (alkaline based) flushing product, especially if changing brands.
  5. Never mix inhibitor or coolant products. Always drain the cooling system and flush completely if switching brands, the coolant appears contaminated or where scale build-up is suspected.
  6. Ensure the correct mixture ratios are maintained when topping up to avoid under treatment, which promotes corrosion. Under treatment can raise the corrosive rate to higher levels than found in water.
  7. Regularly check radiator hoses for signs of obvious expansion, excessive softness, or a crunchy feel on squeezing. Have them replaced if any of these are apparent. Ensure the radiator cap fits tightly and securely.
  8. Radiator fins and core tubes are prone to corrosion from external factors, reducing heat transfer efficiency and increasing the potential for leaks. Inspect the external fins of the core regularly and have them replaced where necessary.
  9. If you are having problems with an overheating engine, do not be tempted to disable or remove the thermostat. Running a car in an overheated condition can have very serious consequences on your cooling system, you might break a head gasket, inflict pre-ignition/detonation damage to the engine or in extreme cases cause complete seizing of the engine.
  10. The fastest killer of radiators electrolysis. Coolant is conductive and any stray current can increase the corrosion of the core at an incredible rate, new radiators can be completely destroyed in under three months. Check to ensure all earthing points are properly connected and making clean contact, especially where aluminium radiator cores are concerned. If you are unsure if your radiator is properly earthed, consult your mechanic or auto electrician.