The coolant level in your car is just as important as the oil level. If you are experiencing rapid coolant loss, it could be due to a leak or, worst case, a leaking head gasket. When a head gasket fails, the coolant mixes with fuel in the cylinder, and during the combustion cycle, it burns. Cars burning coolant tend to overheat and smoke heavily.
Before now jumping to conclusions, it’s important to check for coolant loss the minute you first notice it. I have detailed several places to look for the loss in this article, why these places are essential to examine and the results of not carrying this out.
7 Parts to Inspect When Looking for a Coolant Leak
When looking for a coolant leak on a vehicle, I check these seven items first. You can be sure it’s one of the 90% of the time; if not, I will start inspecting the car for a head gasket fault.
- Leaking radiator – The radiator core tubes and fins can become damaged by impact from debris in the road. Also, the end tanks can corrode on older vehicles; the usual place to look for coolant leaks in a radiator is along the bottom of the radiator casing; you can sometimes see the coolant leaking or spot the damp patches on the end tanks. Leaks in the core are usually evident and easy to spot.
- Coolant bottle – Cracks in the underside of the bottles where the pipes connect to the bottle are common. Sometimes, the hairline cracks can be difficult to spot by eye without removing the bottle, but the staining left behind where the coolant has been dripping makes it obvious you need to remove the bottle and look.
- Heater system – The car’s pipework system for the heater system runs around the side of the motor going into the dashboard; the heater matrix can fail and leak the coolant that runs through it. Occasionally, this can be spotted by either smoke from behind the dashboard or traces of coolant in the footwell.
- Water pump – Water pumps are separate items to the engine that are usually changed when the timing/cam belt is changed. However, when it isn’t, water pumps typically go wrong; with age, the seal between the engine block and the water pump deteriorates, so the pump leaks. You would never try to reseal the water pump if the internals are causing a problem; you would only replace it.
- Water hoses – Most silicone or rubber water hoses under the hood coolant to and from the engine. The hoses split or become weak over time; replacing hoses is very straightforward, and they’re usually purchased as direct replacements from the dealership. Even the clamps that secure the hoses corrode and snap, so you may get leaks, requiring a new clamp to resecure and seal the hose again.
- Overflow pipes – Certain coolant systems have overflow pipes that release excess coolant if overfilled. Although this isn’t usually a problem unless the coolant is overfilled, if the overflow valve is faulty, it can leak coolant even when not overfilled.
- Broken coolant cap – The cap for the coolant bottle is a pressure cap; these can split or break, meaning the water content in the coolant mixture evaporates. Although when this kind of thing happens, it’s not a fast process, it can be noticeable if you’re regularly checking the coolant level and it has dropped significantly.
What if There Is No Leak and the Car Is Going through Coolant?
Unfortunately, if there is no evidence of coolant leaking, but your car is losing coolant, there is only one reason: coolant is being combusted inside the engine. The problem is that it means the head gasket has probably failed.
The head gasket seals the engine’s bottom end and cylinder head together, preventing the coolant from entering the combustion chamber and vice versa; it also prevents oil from entering the coolant system.
There are other indicators that the head gasket is leaking; the most common is loss of coolant, but other indicators to look out for are:
- Overheating engine
- Oil in the coolant bottle
- A build-up of sludge under the oil cap
- Excess smoke coming out of the exhaust
There are special snooping tools and liquid solutions that mechanics use to check for a blown head gasket without the need to strip the engine down to check. If you suspect your head gasket has failed, have your mechanic inspect your vehicle ASAP.
How Much Coolant Loss Is Normal?
Although a sealed system under pressure, due to the high heat temperatures of the coolant, it is normal for some of the water content in the coolant to evaporate. This happens at a prolonged rate, so expect to lose no more than a fluid ounce or two of coolant over 12 months. You can expect to lose a little more than this as a high-mileage driver, but it should never be noticeable. If you find yourself topping up the coolant level regularly, it shows you have a problem that needs inspection.
How Often Should You Check the Coolant Level?
The coolant level should be checked as regularly as once a month, as it is even easier to check than the oil level; it is wise to glance at the coolant tank every time you are under the hood performing other basic maintenance checks.
Topping Up The Coolant
There are minimum and maximum levels on the side of the coolant tank; if the coolant starts to fall below the low marker, top up with a 50/50 mix of coolant and water. You can check the strength level of the coolant and adjust accordingly if you have a coolant strength tester or coolant test strips. In an emergency, you can top up the coolant with just water, but again, the strength will need to be checked as soon as possible. If you’ve added a lot of water, you may need to carry out a full coolant flush.
What Happens if You Ignore Coolant Loss?
It is important not to ignore any amount of coolant loss as it can cause significant damage to your engine over time. Coolant plays a crucial role in regulating your engine’s temperature, and if there is not enough, your engine can overheat. Overheating can result in various issues, such as warped cylinder heads or a blown engine.
How to Prevent Coolant Loss
There are several steps you can take to prevent coolant loss in your vehicle. Here are some useful tips to keep in mind:
- Check your coolant levels regularly – It’s essential to check the coolant level at least once a month or before embarking on a long journey. If the coolant level is low, top it up with the recommended coolant type.
- Look for leaks when necessary – Examine the radiator, hoses, water pump, and other relevant components for any visible signs of leaks if the vehicle is low on coolant. If you notice any leaks, have them fixed as soon as possible.
- Replace worn-out parts – Replace worn-out or damaged parts such as hoses, belts, gaskets, and the water pump, as they can cause coolant leaks.
- Keep the radiator clean – A dirty radiator can cause overheating and loss of coolant. Be sure to perform a coolant flush every two years; this will keep the radiator internals clean.
- Avoid overheating – Overheating can cause the coolant to boil and escape through the overflow tube. To prevent this, ensure your vehicle’s engine is in good working order by performing oil changes and annual services on schedule.
Frequently Asked Questions
Should The Coolant Reservoir Always Be Full?
To prevent problems, the coolant level should always be between the minimum and maximum markers on the coolant reservoir bottle.
Do You Add Coolant While Car Is Running?
Never add coolant to your car while it’s running. Your car’s coolant system operates under high pressure, and if you try to remove the cap while the coolant is hot or the engine is running, hot steam and coolant can forcefully pour out of the reservoir. This can cause severe burns or other injuries, so waiting until your car has cooled down is vital before adding coolant.
Can Overfilling Coolant Cause A Leak?
Overfilling the coolant in your car can cause leaks. The main problem with overfilling the coolant is that it can cause the pressure in the cooling system to increase beyond the recommended level, leading to leaks in weaker components such as hoses, radiators, or other parts.
Can A Car Burn Coolant?
A car can burn coolant, but only when a head gasket fails. When a car’s head gasket fails, coolant can mix with fuel in the cylinder and burn during the combustion cycle. This can cause the vehicle to overheat and smoke heavily.
Final Thoughts
If your vehicle is going through coolant fast, the first call of action is to check for a leak. If you can’t find a leak, then, unfortunately, it will more than likely be a head gasket-related problem, as the engine is burning the coolant away. Most areas where the car could leak coolant are inexpensive to repair; however, if the issue is the head gasket, it’s not a cheap fix.
