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Checking the Cooling System

Coolant is a mixture of antifreeze and water that is pumped around the engine to keep it cool. The coolant itself is cooled as it passes through the radiator. Antifreeze is mainly added to prevent the water from freezing in the winter, but it also acts as an anti- corrosive to protect the radiator from rust.

If the level of coolant falls too low, then the engine can overheat, causing potentially serious damage. Although it's normal to top the levels up occasionally, if you find that you have to top up frequently, have your car inspected in the garage, as you may have a coolant leak.

Check the coolant level once a week, and before any long journey. As the coolant gradually loses its anti-corrosive properties, you should also flush the radiator and replace the coolant every two years; usually during a major service. However, if you notice the coolant has a dirty or rusty appearance, replace it straightaway.

Never open the coolant filler cap while the engine is hot. Wait until it is cool, then place a rag over the cap and unscrew it slowly to allow any pressure to escape.

Checking the Coolant Level

  1. Park the car on a level surface and make sure the engine is cool before opening the bonnet.
  2. Check the level in the coolant reservoir; you should be able to see the level clearly through the plastic container without having to remove the lid.
  3. The coolant level should be between the LOW and FULL marks in the coolant reservoir. If the level is low, top it up using a mixture of 50% antifreeze and 50% water. In an emergency, you can add clean tap water; however, you must add in enough antifreeze to make up the right concentration as soon as you can.
  4. Replace the cap tightly afterwards and wipe away any spills.