Identifying an Engine Coolant Leak

If you’ve got an engine coolant leak in your vehicle you’re probably getting extremely tired of popping your hood every couple of days to check it. It’s a good thing to look under the hood of your car regularly for leaks, worn belts, broken hoses and that sort of thing, but doing that maybe once per month should be good enough to catch problems before they get really bad.

Unless you’re very meticulous with your inspections, most car owners find out they’ve got an engine coolant leak either from a low coolant warning light or from your vehicle starting to overheat. Allowing your engine to overheat is one of the quickest way to do damage to your vehicle’s engine and end up with a hefty repair bill. Allowing your car to overheat is second only to running your engine with low oil in its ability to do quick damage.

The most common causes of overheating are broken water pump drive belts and low coolant levels. The best way to prevent a broken water pump belt is to make sure you change the belt at your manufacturer’s recommended intervals and to take the time to listen to your car for signs of bad bearings in your water pump.

The best way to avoid low coolant levels is to regularly check your coolant level and inspect your engine bay for signs of a coolant leak. Once you’ve discovered a leak, either by lowering coolant levels or from evidence of a leak, you have to identify where the leak is coming from so you can seal the leak and keep your car from overheating.

Identifying an engine coolant leak can sometimes be tricky business. When your engine is at normal operating temperature your coolant is very hot. This means that if it is leaking it will most likely evaporate very quickly leaving very little to no trace of that leak. Engine coolant is also very watery, so unlike an oil leak it can blow, drip or spray to entirely different parts of your engine bay. This means even if you can find coolant on your engine, it can take some extensive detective work to figure out where the leak actually is. Last, your engine coolant travels all through your engine block, the head, the heater core and radiator, sometimes the intake manifold and other places in your engine bay that make just about anywhere a possible leak location.

There are a few easy tricks you can use to help identify an engine coolant leak. First, a great test is to perform a cooling system pressure test. When your coolant heats up it pressurizes your cooling system from the expansion which can expose leaks. A pressure test can similarly pressurize your system which can often make the leak stronger or show up more easily without your engine having to be extremely hot. Second, many auto parts stores sell UV dye and light kits. You can place the UV dye in your engine coolant and drive your car for a few days to make sure the dye circulates through everything. Then, park your car in a very dark place and use the UV light to search for your leak. The dye will show up very brightly under the UV light and should provide a path to your leak point.

The most common coolant leaks occur in the hoses that connect your engine to your radiator or heater core, or other small hoses running coolant to different equipment on your engine. The best way to stop these leaks is usually to replace the hose as they are inexpensive and easy to get to. The other leaks you can find in your cooling system would be in the engine block or radiator. Your radiator is at the front of your vehicle so it’s exposed to road debris, rocks, dust and other things that can poke holes in or crack the thin metal. Your engine block also can form small cracks as the cast iron it is made from is a relatively brittle metal. Since replacing these components can be very costly, it can be much easier to seal these leaks from the inside out. BlueDevil Radiator and Block Sealer is a chemical sealing agent that you can add to your engine coolant. It will then seek out leaks in your engine block or radiator sealing the leak permanently!