Fix car radiator leak | Welcome

A car radiator leak is bad news insofar as the radiator plays an essential role in ensuring that an engine doesn’t overheat.

Telltale signs of a car radiator leak are a sharp decrease in the level of engine coolant, an overheating engine or signs of coolant leaking onto the ground.

In an emergency should you feel that you are experiencing a significant car radiator leak, you should wait for the engine to cool down, add some water and drive the car to your nearest workshop.

Radiator leak causes

Cooling systems and radiators take quite a bashing given the heat generated by modern engines.

By far and away the leading cause of coolant leaks is corrosion. The radiator, its hoses and connectors all collect sediment and rust which can perforate the radiator.

Over-filling the radiator can also cause problems through increasing the water pressure inside the radiator to the point at which it causes damage. A malfunctioning thermostat or heater core can also put too much pressure onto the radiator meaning that you will need to repair the coolant leak.

How to fix a coolant leak

Our advice is to contact an authorised workshop should you experience problems with your coolant system. The workshop is likely to work to a process similar to the following:

They will check the complete cooling system for swelling, collapsed hoses or coolant crusting onto the connections starting with the hoses and their connections.
Next, they will look for broken fins and cracks to the radiator casing.
If they can’t identify where the problem is coming from, they will use a cooling system pressure tester.
To fix the coolant leak, they may add a radiator sealant to the engine while the coolant is cold but with the engine running. This should be sufficient to seal over any small cracks.
If this does not repair the coolant leak, they will need to remove the radiator. They will use a radiator pressure kit to re-pressurise it and then submerge the radiator in a tank of water to identify the leak through the release of air bubbles.
Having identified the leak or leaks, they will dry the radiator out and apply an epoxy seal to fix the coolant leak.
They will ten repeat steps 5 and 6 if necessary.

Find the best coolant for your vehicle.

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