It can be a frustrating thing when you don’t know what causes a car to overheat. For the most part your car’s cooling system probably works pretty well and you don’t give it a second thought. When it overheats, it can leave you quickly stranded and stuck not only with a tow truck bill, but a steep repair bill as well.
Vehicle’s cooling systems today have gotten a lot more advanced than they used to be. The basic principle is the same but the radiators are made with more advanced designs, the fans are much more efficient and the thermostats are less prone to failures. Many car manufacturers today are so confident in their vehicle’s cooling system that they don’t even include a coolant temperature gauge on your dashboard anymore.
Keeping a close eye on your coolant temperature gauge or warning light is one of the best ways to prevent your vehicle from overheating. Once the gauge rises above normal, or the warning light comes on, pull over immediately and turn of your engine. This will stop the input of heat and get your vehicle to start cooling down. Unfortunately, this is just a short term solution but it will keep any further damage from happening to your car. If components in your engine are allowed to get too hot it can cause major permanent damage like warping, cracking, blown gaskets, ruptured hoses or broken thermostats.
If you find your car overheating and you’re close to home you can drive it for short distances and turn it off once the temperature gauge rises allowing it to cool again. This may help you save money on a tow truck but remember to not let your engine get too hot!
Why Is My Car Overheating?
There are quite a few reasons why your car may be overheating. The main goal of your car’s cooling system is to remove heat from your engine block by running coolant through cooling passages and transfer that heat to the air through the radiator at the front of your car. Your water pump is driven by a belt connected to your crankshaft and is the motive force for moving the coolant around the system. If your car is overheating it can either be because the coolant is not moving fast enough, the heat isn’t getting transferred out of the engine to the coolant, or it is not getting transferred out of the coolant to the air through the radiator.
To find out which of these problems you are having, you can take temperature measurements around your vehicle. The best way to do this is using a non-contact thermometer. Non-contact thermometers use the infrared radiation emitted by a warm object to determine its temperature. Measuring the temperature at the inlet and outlet of your radiator, thermostat, and water pump can help you determine if your system is clogged or fouled and what the likely culprit is. If you don’t see a large, uniform temperature drop from the inlet to the outlet of the radiator, you may have a clogged radiator. If you see a large temperature drop across your thermostat or water pump you may have a broken thermostat or a broken water pump. If you don’t see a large temperature rise from the water pump outlet to radiator inlet you may have scaling in your engine block and be in need a system flush.
Before you complete any of these diagnostics you need to make sure your cooling system is filled properly to make sure you get accurate readings. Most vehicle’s cooling systems have an overflow tank or expansion reservoir. As your cooling system heats up, the coolant will expand. As the coolant expands the pressure will rise in the system until it reaches the pressure of the radiator cap. At his pressure, the radiator cap will allow coolant to escape to maintain a constant pressure in the system. This escaping coolant is captured in the coolant reservoir. When you park your car and turn it off, the coolant will cool and contract. The radiator cap will then allow the coolant in the coolant reservoir to be drawn back into the system making sure air bubbles do not form as things cool down.
If your cooling system is not completely full of coolant at all times, it will not operate as efficiently as possible and may be the source of your overheating. You can check to make sure your system is full by checking the coolant reservoir. If it has coolant in it when your car is completely cold, like after sitting all night, then your cooling system should be full and free of air. If you check the reservoir and find it empty, it is an indication that you have a low coolant level, even if it has some coolant in it when your car is warm.
If you find an empty coolant reservoir it is an indication that you have a leak in your cooling system. If this is the case, add BlueDevil Radiator and Block Sealer before you top off your cooling system with new coolant. BlueDevil Radiator and Block Sealer is a special formulated liquid sealing agent that you can add straight to your radiator. BlueDevil Radiator and Block Sealer will not harm your thermostat or water pump, but it will seal a leak in your system whether it is in the radiator or block and in steel, iron, aluminum or plastic.
For more information about BlueDevil Radiator and Block Sealer, visit our product information page here: Radiator and Block Sealer
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