What Overheating Can Do to an Engine

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What Overheating Can Do to an Engine

The first engine was created in 1878, but it has undergone major design changes. Today's car engine is quieter, smaller, and more fuel-efficient than ever. Perhaps most important of all, it's more durable than ever; modern car engines generally don't need service within their first five to seven years. Some car engines can go a decade without a major problem.

Treating the car well lessens a driver's odds of needing to work on the engine, or worse, replace it outright. Despite the car engine's durability, it can't withstand incredibly high temperatures for long periods of time. It's not just the engine that balks at such extremities either; seals and gaskets can suffer irreparable damage after being exposed to temperatures they're not designed to handle.

Long story short, overheating can permanently damage a car beyond financially responsible repair. It may help car drivers to understand how they can avoid this catastrophe and why it happens in the first place.

Causes of Overheating

Anything that lessens an engine's ability to absorb, transfer, and dissipate heat has the capability of overheating an engine. Unfortunately for drivers, there are a lot of potential causes, but some are more common and than others. Many of them are easily fixable by a reputable mechanic and generally involve replacing relatively inexpensive parts.

Low Coolant or Antifreeze

A low coolant level is probably one of the most common causes of overheating. Also known as antifreeze, coolant is necessary to keep the car engine functioning within normal temperatures. The problem has a simple solution: refill the coolant and avoid neglecting the levels in the future. Checking antifreeze levels can be dangerous if a driver doesn't know what he or she is doing. Whenever in doubt, the driver should seek the help of a certified mechanic or someone who is more familiar with cars to help solve the problem.

Faulty Thermostat

Moving from the most common cause to the most frustrating, a faulty thermostat can easily overheat an engine. Basically, a bad thermostat can say to the engine, "The temperature is just right. There's no need for additional cooling," when the temperature is actually too hot. Giving false readings prevents the car's release of antifreeze. After being driven for a while, the car gradually becomes hotter and hotter, eventually billowing smoke or stalling out. The solution is replacing the thermostat,, and the car should no longer overheat, as long as that was the only problem.

Low Motor Oil Levels

A car with a low oil level may overheat because oil carries heat away from the engine. Running low on oil is harmful in other ways too; for example, oil acts as a lubricant, and no oil can lead to excessive wear on some parts because they're not adequately lubricated. Drivers can refer to their car manuals or local car dealership to determine how much oil their car needs and how often it should be changed or topped off. Different cars require different kinds of oil. Drivers should never put a random oil in their car. The price range of motor oil varies a lot, depending on the type.

Overheating Damage

In general, the parts to prevent overheating are less expensive than fixing the damage overheating has done. There are exceptions to this rule, of course, but prevention is almost always better than cleaning up the mess afterward. Have no doubt; damage due to overheating can be messy, often with antifreeze creating the destruction.

Cracked Head Gasket

A head gasket prevents antifreeze from leaking. When it's cracked, antifreeze is free to wreak devastation on the engine it's supposed to keep cool. This is just one problem that can occur should a head gasket break, though. While head gaskets aren't expensive, replacing them is time intensive and generally not something a frugal person wants to pay for in labor fees.

Warped Cylinders

Cylinders are part of a car's engine. They're metal tubes in which pistons move through. If antifreeze leaks into a cylinder, its walls can degrade and warp. Cylinders are incredibly important; they're fixable when they break, but it's often not worth the money involved. Some mechanics recommend replacing the entire engine if a cylinder "dies," especially in older cars where the driver could easily spend more money than the car is worth.

Pricing the Parts

An overheating engine is rarely a reason to ditch a car,, but sometimes the parts to fix it are expensive. Some are more expensive than others; for example, refilling a car's antifreeze is incomparable to fixing a warped cylinder, since the latter is so pricey.

Car Parts

Estimated Price

Maintenance Tips



Replace after 30,000 miles

Motor Oil


Replace after 7,500 miles

Head Gasket


No upkeep unless blown



No upkeep unless other problems occur



No upkeep unless readings seem off

For drivers on a budget, they should try shopping around for the cheapest parts. Online shops are a great start, since they provide such a wide selection and compete against each other. In addition, they can also shop around for auto shops to actually install the part. Auto shops differ in their pricing structures, with some offering less expensive fees on labor.

Signs of an Overheating Car Engine

All drivers should be aware of the damage overheating can cause. In addition, if overheating happens, they should have a general idea of what's involved in repairing the car. Unfortunately, this knowledge is fairly useless if they don't also know the signs of an overheating car engine. While prevention is key, and regular car maintenance significantly reduces the odds of a car overheating, sometimes it happens anyway. By learning to spot an overheating car, drivers can quickly turn the car off to prevent further damage.

Steam or Smoke

Any time a driver sees steam or smoke billowing from under their car's hood, they should stop the car. This is never a good sign. Sometimes it's as simple and harmless as spilled oil burning off the engine, while other times it indicates an overheating engine. Whatever the case, it's generally worth having it inspected by a reputable mechanic.

Dashboard Warnings

Unfortunately, dashboard warnings often aren't noticed. Still, unless a car's thermostat is broken, the car should be telling the driver that the engine is running hot. In newer cars, there is usually a light that comes on when the car begins to overheat.

Hot Air from the A/C

Hot air coming from the car's air conditioner doesn't mean the car's currently overheating, but it most likely will sometime in the near future. In most cases, putting antifreeze in the car solves this problem.

Buying Car Parts on eBay Motors

Almost everything car-related can be found on eBay Motors,, from antifreeze to specific car parts. To find these things, use the search bar found on any eBay page to enter keywords like "thermostat&" or "motor oil.." Once the results load, narrow them by creating a price range or adjusting other preferences.

eBay Motors has thousands of categories to navigate through. Fortunately for shoppers, they're sorted into branches and easy to navigate. Whenever you feel lost, just enter another keyword into the search bar to be directed toward a list of results. You can be as specific as you'd like; if there are no results, trim it down a bit.

Choosing an eBay Seller

Since eBay Motors carries millions upon millions of products, it's not unusual to find several sellers offering the same product. To choose between them, look at their feedback percentage. While good feedback doesn't guarantee a brilliant seller, it does mean past eBayers were satisfied with the service received.

Next, read the seller's return policies in case the part doesn't meet your standards. Some sellers offer a "no questions asked" 30-day return, while others are much more selective about which products they'll accept and in what timeframe.


Knowledge is key in avoiding the problem of having an overheated engine in the first place. If a car is taken in for routine maintenance, its likelihood of overheating is slim. Overheating is generally caused by negligence; for example, trying to go 20,000 miles without an oil change or ignoring dashboard warnings. Sometimes things just happen, though; in this case, buying a part from an online store is quick and convenient.

For safety's sake, drivers should never continue driving a car they believe is unsafe. Instead, they can call a towing service or, in many cases, their mobile phone service provider or credit card company. It may sound wacky, but service providers of all kinds will sometimes offer roadside assistance for free. A roadside assistant rarely actually fixes the car; instead, the provider will tow the car to safety, whether it's a nearby auto shop or the driver's home.

Drivers should double-check and confirm that the part they're buying will fit their specific car, in addition to whether or not it'll fix the problem. It's important to consult with a certified car mechanic should a driver feel uneasy about replacing even the simplest part. Often, detailed instructions can be found online.

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