How Long Does Coolant Last?

Your car’s coolant system centers around a coolant that runs through the system. Most folks know that the coolant is added through the radiator and that the radiator should be full. However, there are times when the radiator is not full that little line on its neck. That means that coolant does not live forever. Read on to find out how and why the coolant in your car becomes low.

The Need for Coolant

Internal combustion engines must have cooling systems. Most designs use a radiator filled with a mix of ethylene glycol antifreeze and water which is designed to remove heat from the engine. The automotive cooling system is comprised of two main parts: the liquid cooling part and the air-cooling part. Both parts of the cooling system must depend upon air to some degree, but only one part uses liquid. Older automobiles usually have air cooling systems, while a few newer models use air. However, most newer models use a liquid cooling method.

The liquid cooling system is more complex than the air. The liquid cooling is typical a type of antifreeze made of mostly ethylene glycol. There are passages in the engine block and also in the engine heads. A water pump circulates the coolant (view on Amazon), which is moved around by hoses and cooled in the radiator. The coolant travels through the parts of the engine, absorbing the heat.

The heated coolant travels through rubber hoses to the radiator. Natural air coming in from the grill cools the coolant as it passes through the radiator. The coolant then returns back to the engine and the process starts all over again. The cap on the radiator controls the pressure within the cooling system. A thermostat that regulates the coolant temperature. The engine will definitely overheat due to a lack of antifreeze or from antifreeze leaks or not circulating.

How Long does Coolant Last?

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When there are no problems in the coolant system or elsewhere that would a loss of coolant prematurely, the coolant should last for 3 years. That is, if the coolant is mixed with tap water. If the coolant is mixed with distilled water, the coolant can last about 5 years.

Causes of Car Losing Coolant

Several things cause the loss of coolant prematurely. The problem can originate from most anywhere under the hood. The coolant passageways could be blocked, or there simply is not enough coolant running through the system to keep everything cool. Most vehicles are equipped with a Low Coolant light that warns the driver that the coolant is low. Here are the most common causes of coolant leaks in the internal combustion system:

Extreme heat – The engine gets extremely hot and forces the liquid out. When the coolant has air, it does not absorb heat from the engine the same way. If temperatures under the hood get extremely hot, the coolant will start to evaporate. These things will likely only happen if your radiator fan is not spinning. Or, it could be the coolant is naturally evaporating over time. However, under normal operating conditions, you should be able to keep the coolant topped off.

Coolant leaks – Coolant can leak out of the system in several ways. When the engine heats up, the coolant volume expands inside the hoses and the engine. The overflow of coolant collects inside the surge tank. The surge tank hose may become worn out or damaged, These issues promote blown head gaskets, engine overheat, and leaks that cause serious damage to the engine and fueling systems. The leaks may occur in the heater core, radiator, thermostat housing, freeze plugs, or the head gasket. Several other things cause and contribute to coolant leaks. The ac compressor is designed to prevent the coolant from leaking while being pressurized. When the ac compressor becomes worn, the bearings are damaged. The coolant is then allowed to leak through the bearings.

Damaged gasket or seal -The internal combustion engine uses many types of gaskets and seals to keep the liquids, including coolant or oil contained and moving about. Many of those gaskets and seals are used inside the intake manifold and the throttle body. Over time, the seals can wear out, become dry, and start leaking. Combustion gasses coming from the cylinders enter the coolant system and cause bubbles. The head gasket is a special seal that is located between the engine block and cylinders. When this gasket becomes damaged or blows, leaks occur under the exhaust manifold.

Bad radiator core tubes– When the cooling system in the vehicle has not been serviced in a while, the old fluid sits and accumulates debris or sediment and even rust that blocks the core or grill over time. The cooling fins in the radiator corrode and coolant leaks occur. The engine requires consistent flows of coolant. If the leaks are not addressed in a timely manner, the radiator becomes permanently damaged. It can also cause damage to the head gasket or cylinder head often characterized by radiator damage, engine overheat, and bubbling in the coolant reservoir.

Bad heater control valve – The heater control valve allows the coolant to flow from the engine to the heater core. When the heater control valve is open, the warmed engine coolant can pass through to the heater core to produce hot air through the vents. When the valve fails, the coolant is leaked. The valve becomes worn over time and begins to crack. The coolant flows through the crack.

Blocked Radiator Core– When the cooling system in your car has not been serviced or flushed in a while, the old fluid accumulates debris and rust that blocks the core or grill over time. The cooling fins in the radiator corrode and coolant leaks occur.

You Treat Your Car Like Shit – If you fail to look after components in your car, it can lead to several components failing which can cause coolant problems. Maintaining your vehicle is a crucial process that needs to be done by every car owner and it prevents you from experiencing a lot of problems. Failure to look after just one component can cause a knock on effect and this can be felt in other areas of the car.

If you want to avoid coolant problems or other issues and save $100s of dollars that you’ll spend at the auto repair shop, you’ll need to service your vehicle often – you can use our mechanic-rated Auto Maintenance and Repair Manual to do this. It’s basically what mechanics use to go through your vehicle to check if there are any problems that need fixing. As soon as they notice the most minor problem, they’ll ask you to fork out some money even though it’s a problem you can fix yourself in minutes – the manual will teach you how to maintain your vehicle every few thousand miles and it’ll teach you how to fix minor problems that mechanics will ask you to pay for; saving you money in the long run.

A lot of our readers have the Auto Maintenance and Repair Manual printed on their garage wall and 92% of them haven’t visited the auto repair shop in the last year because they know what to do to avoid problems. All it takes is giving your vehicle a little attention every few thousand miles and you’ll never spend money at the workshop again.

Symptoms of Car Losing Coolant

If your car is losing coolant, there are a few signs. It is extremely important that you look for these signs and find leaking problems early. Here are the most common signs that your car is losing coolant:

Temperature Gauge on Hot – if the radiator fan is not working, your temperature gauge maybe rising toward hot. The coolant is no longer being cooled down as it circulates through the engine and the thermostat picks up the change. The temperature gauge on your dash moves toward HOT and remains there until you turn the car OFF.

Coolant on the GroundIf your engine is overheating, it may just mean you need to add more coolant. The leak may accumulate in pools of green fluid under your car. (The coolant can be different colors depending on the manufacturer. If there is coolant on the ground under your vehicle, it could be because it got so hot, the coolant boiled over and spilled from the coolant overflow tank. It can also mean that you have a coolant leak which caused the engine to overheat.

Sweet SmellWhen there is a coolant leak you will smell a sweet smell coming from under the hood. Actually, you can smell it while you are driving and after you’ve driven. That is the toxic ethylene glycol running through your cooling system. However, you still have to find the leak. When you smell the sweet odor, there are problems that will escalate if you do not fix it.

Hot smell under hood – Less coolant means your car is very likely overheating. If your vehicle smells hot after you turn it on for a time or you smell it when you get out of it there is a problem with the cooling system. When the engine overheats, the metal, rubber, and plastic components give off a distinctive smell that many describe as “smelling hot”. The smell may also enter the vehicle through the AC vents.

How to Preserve Coolant

When the vehicle is serviced, there are a few things that can preserve the coolant or at the least minimize loss. That is why it is very important to have your vehicle serviced regularly. If you have the tools and skill, you may be able to service it yourself. Here are things you can do to prevent coolant loss:

Park in a cool place – Coolant has some degree of water in it, so it can evaporate. The parts under your engine can become hot even when you are not driving. If you live in an area with smoldering heat, find a cool place to park your vehicle so that it will be cool when you set out.

Bleed the Cooling System– Some problems mean you just need to start over. There are several methods for you to start over in your cooling system. This method is the bleed screw method of bleeding the cooling system. To use this method, follow these steps:

  1. Park your car in a safe place.
  2. Make sure your car is OFF and wait until the engine is cool.
  3. Carefully remove the radiator cap
  4. Check to see if the coolant is at the recommended mark. The radiator should be filled to the bottom mark of its neck. If there is not enough coolant, add more to bring it up to the mark. The radiator should be filled to the bottom of the neck of the radiator.
  5. Now, add some coolant to the reservoir. The coolant level in the reservoir should be on “cold”.
  6. Replace the radiator cap.
  7. Locate the bleed screw on the engine. Once you find it, before you remove the screw, slide a pan under the vehicle to catch fluid that will run out when you remove the screw.
  8. Turn your car ON.
  9. Let the car run on idle for at least 20 minutes to allow the engine to rise to the operating temperature. Touch the radiator hose at the end of the 20 minutes to see if it feels warm.
  10. If the hose is warm, remove the bleed screw by slowing turning it counterclockwise using a wrench. Only turn the bleed screw, do not completely remove it or you may be seriously burned by the boiling coolant.
  11. When all of the coolant has run into the pan, retighten the bleed screw.
  12. Turn the car OFF and wait at least 15 to 20 minutes for it to cool.
  13. Refill the radiator with the right amount of new coolant. Fill the radiator to the same mark at the base of the radiator neck. If needed, add some coolant to the reservoir.

Get Help from Certified ProfessionalsEvaporating coolant or coolant leaks are no small matter. If they are ignored, your car repairs can quickly become expensive. Many problems associated with the cooling system cannot be solved with a bit of patching up. Certified technicians know how to replace coolant or service your cooling system the right way.