Before we get to how to fix a coolant leak, let’s talk about why it is important to fix your leak quickly. If your car is leaking coolant, it will run normally until the coolant level gets too low. Once it is low, there will not be enough coolant to keep your engine at the normal operating temperature and the engine will overheat. If your engine overheats, it can cause significant damage to the block, heads and other components. To learn more check out our article on engine overheating.
Fixing your coolant leak quickly will ensure your vehicle has the proper coolant level to stay cool and safe. Coolant leaks can come from a variety of places in your vehicle and where the leak is will dictate the best solution.
Possible Coolant Leak Locations:
- Heater core
- Head gasket
There are at least 4 hoses associated with the cooling system in your vehicle, but possibly many more. There will be a hose that carries coolant from the bottom of the radiator into the water pump and another hose that carries coolant from the top of the engine back to the radiator. There will also be hoses that carry coolant to and from the heater core, which is most likely located under your dashboard so the hoses will travel from the motor back to the firewall, or the rear of the engine bay. Overtime due to heat and age the ends of those hoses can become brittle and begin to crack where they are attached causing small leaks. In this case, the best thing to do is purchase a new hose and clamps and replace the broken hose.
The thermostat is usually on the top of the engine, but in cases, as in many Subarus can be located on the bottom of the engine. It’s likely near the water pump and is closed in a housing that is near one of the hoses going to the radiator at the front of your vehicle. This housing is usually bolted on so that it can be easily removed if you need to replace the thermostat. It is possible that the thermostat housing can develop a leak where it is bolted together. In this case, consider replacing the thermostat housing gasket. Since you already will have it apart, consider replacing the thermostat as well since it is a relatively inexpensive part.
As discussed above, your heater core is located under your dashboard near the cabin ventilation fan. Warm coolant from your engine is pumped through the heater core, then your cabin ventilation system uses that to heat the air in the cabin of your vehicle. If the heater core is leaking you will find coolant on the floorboards of your vehicle, most likely on the passenger side. Removing the heater core can be an expensive and tedious job requiring the removal of a significant portion of the interior of your vehicle. To repair the leak in your current heater core use BlueDevil Pour-N-Go. BlueDevil Pour-N-Go is a non-particulate chemical based leak sealer that reacts at the temperature differential created at the leak point in your cooling system. BlueDevil Pour-N-Go will create a chemical weld at the leak permanently sealing the leak in your heater core without expensive removal. Simple add BlueDevil Pour-N-Go to your vehicle’s radiator and allow up to 2 days drive time for the leak to seal.
If you discover a radiator leak you can repair it by using BlueDevil Pour-N-Go to seal that leak in just the same way. Since your radiator is in the front of your vehicle and a relatively fragile piece of equipment it is not unusual for it to get holes from rocks or road debris. BlueDevil Pour-N-Go can save you from the costly repair of purchasing a new radiator.
You can tell if you have an external coolant leak from your head gasket if you discover coolant leaking from bellow your exhaust or intake manifold. We also recommend you check for other signs of a head gasket leak. External head gasket leaks must be sealed very quickly as they will expand over time if they are left untreated. If you have an external head gasket leak use BlueDevil Head Gasket Sealer. BlueDevil Head Gasket Sealer can seal the head gasket leak even in vehicles with large cooling capacities, like V8 engines or truck engines, and is powerful enough to stop even large leaks. You can purchase BlueDevil Head Gasket Sealer here.
If you’ve got some other cooling system questions, we’ll talk through those as well!
What can Cause an Antifreeze Leak?
Antifreeze leaks can be caused by a variety of things but the two most common factors are age and dirty coolant. If you’ve got wear products dirt or oil in your coolant it can accelerate wear in your system leading to leaks in your water pumps or at gaskets or o-rings. Flushing your cooling system is the best way to stop this type of leak. The years are also rough on cooling system components causing plastic to get brittle and hoses to get swollen which are the most common causes of antifreeze leaks. In this case, there is no way to prevent a leak, but simply to watch for signs of a damage to a cooling system component.,
How do You Know if You Have a Blown Head Gasket?
It can be easy to jump to conclusions about cooling system leaks and assuming any mystery leak is a blown head gasket. We would strongly recommend checking for multiple symptoms of a blown head gasket before jumping to that conclusion.
Why is My Car Leaking Coolant?
The only two reasons your car could be leaking coolant is due to a part failure or an overfilled system. Coolant expands as it gets hot and flows from your vehicle’s radiator into the overflow tank. If the overflow tank is too full coolant will spill out of that reservoir and may look like a leak. If this is the case, you should only see coolant overflowing the tank 1 or 2 times and after that, the excess coolant will be removed from the system and you shouldn’t see any more overflow.
How do You Know if You Have a Coolant Leak?
Checking the coolant level regularly is the best way to find out if you have a leak. Remember your coolant expands changing the level so you need to check the level when your vehicle is either all the way warmed up, or completely cold. If you notice the level dropping steadily then you’ve got a leak somewhere. Many vehicles have a sensor in the coolant reservoir that will illuminate a light or message on your dashboard when the reservoir gets too low so if you see that message add coolant and check for leaks.
If you do find a leak, remember BlueDevil Pour-N-Go and BlueDevil Head Gasket Sealer are guaranteed to seal your cooling system leak easily and permanently without costly replacements or mechanics bills. You can purchase any Blue Devil products from our partnering local auto parts retailers like:
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