How can one tell if the radiator in a car is leaking?


What are the signs or symptoms of a leaking radiator in a car? How can I diagnose a leaking radiator problem? Find the answers to these questions here now!

It shouldn’t be new anymore to you guys that puts out some really helpful car maintenance tips and advice every once in a while. In this one, we will be discussing and addressing radiator leak issues.

It’s always strange when you see on your dashboard that the temperature gauge is reading high or you see the temperature warning light coming on. You should know already that your vehicle has a cooling system related problem and this may be caused by some type of leakage – it might be in some other components or the radiator itself.


There are signs which determine whether your radiator is leaking or not, check out!

The first thing that you should do is to make sure that it is the coolant which is leaking and not some other fluid. Remember that the coolant is also often times referred to as “Antifreeze”, but on a technical note, the coolant is actually a 50% mix of antifreeze and 50% water. By using the see-through overflow tank in your car, you can easily check/confirm the coolant level present.

If you check and see that the coolant level is low or the tank is empty, the next step you should take is to check the liquid level in the radiator of such a car, but this should only be done when your car’s engine is totally cool. You just need to note that the presence of little to no coolant in a vehicle’s cooling system cause engine overheating and/or makes the cabin heater in the car blow cold air.


Radiator Leaks can often time be easily detected by just looking through the cooling system under the hood

Now, once you have done the necessary check and realized that you are losing coolant in your vehicle, the radiator is a very good place to start your diagnosis of this problem. Sometimes radiators leak spots can be easily found e.g. a puddle underneath the radiator itself – but some other times, they can be tricky to detect. The advice for diagnosis is to not just above the radiator rather, to check all angles and pay more attention to the bottom area. When there is rust inside of a radiator, holes form the road dirt/debris can cause coolant leaks too. Even if you have an aluminium type radiator, it can also corrode and develop some pinhole leaks.

The antifreeze usually comes in various colours – pinkish-red, yellow, green for example – and will feel like slimy water kind of while also having a sort of sweet smell too. If you look and can’t find any point of the coolant seeping or dripping, look out for rust, tracks or some sort of discolouration on the radiator itself. Those are actually the “telltale” signs of where the radiator must have been leaking.

If after all these checks, the radiator stills seems to look OK, there are several other possibilities of leaks in the cooling system which includes the hoses coming from the radiator to the vehicle’s engine, the reservoir tank, thermostat, engine block, water pump, radiator cap, heater core (this is a small radiator which circulates hot coolant liquid into the dashboard for heating the passenger-compartment) and other components.

  How to determine if your radiator is bad, leaking, or defective. - VOTD

Also, a blown gasket right between the cylinder head and the engine block can be allowing some coolants inside the combustion chamber thereby creating a problem which must be addressed as soon as possible by an expert mechanic. You may notice some thick white smoke/fume coming out of the vehicle’s tailpipe in this scenario.


If you did all you could but still couldn’t find the leak, just get an expert mechanic to check it for you. There various measures that we could recommend but our best advice will still be that you seek professional auto help to avoid diagnosing, detecting and fixing the leak issue once and for all.

Meanwhile, if you want more tips and advice like this which will help you keep your car in good shape for a long time then, navigate here: -> Car Care

Oluwaseun Solomon