Knowing how to cool an overheated engine is an important skill for any licensed driver. Being able to diagnose and repair your own problems can get you back on the road quickly, avoid costly mechanical problems, and help you know when to seek professional help.
Method 1 of 3: Dealing with an Overheated Engine
Step 1. Avoid panicking and stop as soon as possible
While an overheated engine is serious, it will not cause immediate harm to you. If the temperature gauge reaches the red dot or you notice steam coming from the engine, slow down and stop as soon as you find a safe place. If you notice white clouds coming out of the engine, it is not smoke but steam and you have a little time to stop. If you can't do it right away, you'll need to do the following:
- Turn off the air conditioning and open the windows.
- Fully activates the heater and fans to extract heat from the engine.
- Turn on your hazard lights and drive at a slow, steady pace until you can stop.
Step 2. Raise the hood when steam is no longer coming out
If the car is not too hot, turn it off and raise the hood slowly. If it is extremely hot to the touch or if you see steam coming out, it is recommended that you wait until it cools down to be able to raise it completely. Opening the hood will help dissipate some of the heat from the engine.
- Turn off the engine and leave the key in the "on" position. Your lights, dashboard, etc. they should still be on. This will allow the fans to keep running without your motor, which will help speed up the cooling process.
- Let the engine cool completely before touching it or opening the radiator cap. This cooling process can take 30 to 45 minutes, but it will prevent you from sustaining dangerous burns.
Step 3. Check the upper radiator hose
Squeezing the top hose can help you determine if your system is under pressure and therefore know if it is safe to remove the radiator cap. If it feels firm and difficult to tighten, then the system is probably still under pressure and you should not remove the radiator cap. If the hose compresses easily when you squeeze it, then it is probably safe to remove the radiator cap.
Use a rag or towel when handling the hose, as it can be very hot
Step 4. Never remove the radiator cap while the engine is hot
The pressure and steam inside can shoot a liquid stream towards your face. Be careful and leave the radiator cap on for as long as possible. If it feels hot to the touch, leave it there.
An overheated engine can have the coolant as hot as 127 ° C (260 ° F). Inside a closed system, it will not boil. However, once exposed to air, it will boil and can cause severe burns. Wait until the system is cold (or at least not that hot)
Step 5. Twist the radiator cap
Use a towel or thick cloth to gently twist the cap. The cap will expose the liquid inside the radiator or expansion tank to the atmosphere. If the radiator cap does not have threads, you will need to press down after loosening it in order to clear the safety lock. This will allow you to remove the plug completely.
Step 6. Check the coolant reserve tank once the engine has cooled sufficiently
This usually takes 30 to 45 minutes. The reserve tank looks like a white plastic milk jug and connects to the radiator cap. There is usually a mark on the side that will let you know how full it should be.
Step 7. Check the engine for leaks
The most common cause of engine overheating is a leak in the cooling system. Look for a green fluid in the engine or under the car, especially if the coolant is low or empty. However, refrigeration systems need pressure to function, so even a small leak that has not drained much refrigerant can cause problems.
- Coolant typically has a sweet odor and can show up in hoses, under the car, or around the radiator cap. It flows more like water, unlike oil, which has a thicker consistency.
- The coolant is often green in the case of older models, but the color may vary depending on the make and model of the car.
Step 8. Refill the coolant after the car has cooled down
If you have coolant, add some to the car once it has cooled down, usually after 30 to 45 minutes. Open the radiator cap and pour some in for about 3-5 seconds. If you have water, mix the coolant and water in similar parts and add them. Most engines are made to run on a fair mix of coolant and water.
In an emergency, you can put water in place of the coolant, although you shouldn't use it for a long time
Step 9. Restart the car after it has cooled down and check the temperature gauge
Does it go back up to the red dot? In that case, turn it off again and wait another 10-15 minutes for it to cool down before driving. If not, keep driving until you see a mechanic.
Step 10. Call a tow truck in case the problem doesn't go away or you notice major problems
If there is a leak in the cooling system, oil is leaking, or you cannot cool the engine, contact a tow truck immediately. Engine overheating can completely ruin an engine, ruining your car if you're not careful.
If you have the urge to drive the car, be sure to let it cool down as much as possible before starting it again
Method 2 of 3: Driving with an Overheated Engine
Step 1. Note that you can continue driving after the temperature gauge drops again
However, don't do it for long if you can help it. Sometimes you have no choice but to keep driving until you can get help.
- If your car doesn't overheat again, you may just have overheated from a variety of factors (air conditioning on, hot day, stop-and-go traffic). However, you need to keep an eye on the temperature gauge whenever possible in order to avoid further problems.
- Most cars are calibrated to feel overheating before the engine takes serious damage, giving you a little time to fix the problem. However, this does not mean that you should ignore the indicators.
Step 2. Turn off the air conditioner
Air conditioning uses energy from the engine to cool the car and it is not good for the car to be subjected to more stress than it can handle. Instead of using the air conditioner, open the windows to cool the interior.
Step 3. Turn the heating on to maximum
While this seems counterproductive, car heaters work by sucking the heat produced by the engine and pulling it inside. So turning on the fans and the heater on full blast will draw the hot air out of the engine and cool down the car. However, it can be a bit uncomfortable.
- Rotate the vents so they point toward the window to prevent the cab from getting too hot.
- Alternatively, you can set the heat to the "defroster" setting to prevent it from blowing directly at you.
Step 4. Put the car in neutral and turn the engine on
Increase the revs to 2000 rpm with the car in neutral. This will help the engine and fan circulate the air more quickly, transporting cool air and coolant into the engine and helping you dissipate some of the car's heat. If you're in traffic that makes you stop and resume driving, this might be a great way to keep your engine running when the car can't.
Step 5. Add water to the radiator if you don't have coolant
While not recommended for long trips, water will help keep your engine cool in an emergency. Add warm water to the radiator, but only after the engine has cooled down. Cold water can crack the engine due to the extreme change in temperature.
Step 6. Drive for short stretches, turn off the car, and repeat the process if you need to keep moving
If you absolutely must drive with an overheated engine, keep an eye on the temperature gauge. Every time it gets hot, stop, turn the car off, and wait 10-20 minutes while it cools down. This is not good for the engine, but it is better than trying to drive and cause a total meltdown.
Step 7. Keep in mind that you will probably need to go to the mechanic in case your car chronically overheats
If your car keeps overheating, has a leak, or can't start, you need to go to the mechanic. Even if these tips help you “deal” with overheating when it occurs, there is probably a more important problem that needs to be fixed before a major melt occurs.
Method 3 of 3: Avoid Overheating
Step 1. Drive at a slow, steady pace instead of stopping and moving forward in traffic
Stopping and moving on puts stress on the engine that can overheat it, especially in older cars. Release the brake and let your car crawl knowing that you will probably have to stop again when you get to the bumper of the next car.
Get in the habit of checking the temperature gauge on red lights and stop signs
Step 2. Open the windows instead of using the air conditioner to cool the car
Air conditioning uses energy from the engine to cool the air in the car, which puts additional stress on it. The first thing to do when the engine overheats is to turn off the air conditioning, but avoid using it entirely if you are afraid that your car may overheat for some reason.
If you haven't had an inspection in a long time, if you find a radiator leak, if you're having trouble with your air conditioning, or if you don't have much refrigerant left, avoid using the air conditioner altogether
Step 3. Change your car's oil regularly and have the fan checked simultaneously
Old oil can lead to overheating, especially in combination with low refrigerant or other problems. Every time you change the oil in your car, ask the mechanic to check the fan as well. Finding a problem now can save you a costly repair down the road.
After turning off the car, you should hear the fan whirring as it continues to run to cool the vehicle
Step 4. Refill the coolant at the beginning of the summer
Check the coolant reserve and make sure the levels still correspond to the markings on the sides. If they are a little low, mix water and coolant in equal parts, and add them to the recommended level. This is particularly important if you live in hot areas.
When checking the coolant, take 2-3 minutes to look for any leaks. The coolant is usually green in color and smells sweet. Check under the car, around the engine, and over any hoses or radiator parts that you can see
Step 5. Keep an emergency kit in your car in case of an overheating problem
You don't want to be stranded in the middle of nowhere with a dead engine. A simple prep kit will help keep you and your engine safe, especially if you need to keep driving until you find a mechanic. You will need to pack the following:
- additional refrigerant
- about 1 gallon (4 L) of water
- a toolkit
- a flashlight
- non-perishable food
- a blanket
- a straight razor blade
- American tape
- flat head screwdrivers