How to stop engine coolant from leaking

Written by robert russell
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Leak's in a car's cooling system can have dangerous consequences for a car and can leave you stranded. In most cases coolant leaks can be visually diagnosed by opening the bonnet of the car and visually inspecting the car's hoses and cooling system. If you are lucky it will be possible to do a quick and temporary fix that will allow you to get your car to mechanic for a professional repair job. The essential thing to remember is not to drive car when the coolant level is dangerously low.

Skill level:
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Things you need

  • Rags
  • Duct tape
  • Epoxy or plastic welding material
  • Radiator sealant
  • Screwdrivers
  • Adjustable wrenches

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  1. 1

    Inspect the coolant level on a regular basis. The most obvious signs of a coolant leak is low levels of coolant in the coolant reservoir. Other signs include coloured puddles under the car, and burning smell when the coolant drips on a hot engine. The worse case scenario is white smoke coming out of the exhaust system. This indicates that you have a head gasket problem.

  2. 2

    Examine all of the hoses on the radiator and coolant reservoir. If the hose has a pinhole sized leak it is sometimes possible to see the coolant dripping from the hose. Other signs of bad hoses included blisters and bulges, soft spots, hardening, and cracks. Perform a quick fix by cleaning the hose with a rag and wrapping the damaged area tightly with duct tape. This is only a temporary fix. Replace all damaged hoses with new hoses.

  3. 3

    Check the coolant reservoir for cracks and holes. Coolant reservoirs are made from plastic and can be easily cracked. If the coolant reservoir has a crack allow the car to cool down. Remove the reservoir. Thoroughly wash and clean it. Patch the crack with a plastic welding material or epoxy. Allow the patching material to dry and replace the coolant reservoir.

  4. 4

    Inspect the radiator for signs of coolant leaking. The radiator itself is prone to damage from stones and road debris and from general ageing. Pinhole sized leaks in the radiator can be temporarily repaired with a radiator sealant product such as Alum-A-Seal or Bar's Leak. These products and similar products are available at auto parts stores. Allow the engine to cool down. Remove the radiator cap and empty the contents of the sealant into the radiator. Run the engine for fifteen to twenty minutes. Radiator sealant works well for pinhole sized leaks and smaller holes as well, however, this is a temporary fix. Take the care to the mechanic and have the radiator professionally repaired.

  5. 5

    Take a close look at the water pump. The gasket and O-seal on the water pump are another possible source of coolant leakage. Look for signs of discolouration and liquid coolant on the outside of the water pump. Replace the water pump if it is the source of the problem.

  6. 6

    Take your car to the mechanic if you are unable to diagnose the problem. If the coolant reservoir is continually reading at a low level and you cannot locate the source of the problem, then there is an internal leak somewhere in the cooling system that requires professional attention.

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