How to Check a Vehicle’s Coolant or Antifreeze

The radiator in your vehicle cools your engine and needs water and coolant (antifreeze) to function. Keep the following points in mind as you check the level of the liquid in your cooling system and add more, if necessary.

Rather than open the cap on the radiator, just check to see whether the liquid reaches the ‘full’ line on the side of the coolant reservoir shown here.
• It’s part of the coolant recovery system. If the liquid doesn’t reach the ‘full’ line open the bottle, add a 50/50 mix of water and coolant until it does.
• Some coolants are premixed, check the bottle to see whether you need to add water or just use it as is.
• Some coolant recovery systems are pressurised and have a radiator pressure cap instead of a normal cap.
• Coolant is usually red, green, blue or yellow. You need to know
• If it looks colourless, rusty or has things floating in it, flush your cooling system and add new coolant.
• If the coolant has a sludgy oily surface, immediately take the car to your mechanic to check for internal head gasket leakage.
• While carrying out this task check the radiator hose too.
• They are the big hoses that go into the top and come out of the bottom of the bottom of the radiator. If they are leaking, cracked or bulgy they need to be replaced.

Important to remember
• Never add coolant to a hot engine!
• If you need to add more liquid, wait until the engine has cooled down.
• Don’t open the caps when the engine is hot;
• If you do hot coolant may be ejected.

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How to Check a Vehicle’s Coolant or Antifreeze