None of us want to have to pay to repair any part of our cars but sometimes it’s unavoidable. When it comes to dealing with a blown head gasket cost, knowing what range you should expect to be hearing from your mechanic will ensure you’re informed and prepared. You’ll be armed with the knowledge to ensure you’re not taken by surprise, as well as some perspective on how a blown head gasket repair compares to other repairs your car may need to undergo. With that in mind, the average cost for a blown head gasket repair is in the $1,000 to $2,000 range with some rare cases possibly going as high as $2,500.
What is a Head Gasket?
One of the most infuriating things about fixing a blown head gasket is the fact it seems like such an insignificant part of your engine when you see it. It’s very thin and often made from multiple layers of steel and elastomer and riddled with holes. It’s meant to sit between the engine block and cylinder heads to create an airtight seal in a combustion engine. This allows the combustion reaction to take place safely within the cylinder and seals out things like coolant and oil. If you don’t have a well-sealed gasket in place, then you don’t have the necessary compression for the engine to function.
Some older gaskets and those in some higher end automobiles may be made from copper rather than the multilayer steel. A copper gasket is usually very durable so if you have a blown gasket, odds are it’s not a copper one, but it is possible. Copper usually makes for an exceptional seal between the engine block and the cylinder head as the metal is soft enough to fit snugly when everything is tightened in place.
Composite head gaskets appear in older vehicles and they are made from materials like asbestos and graphite. This is arguably the least reliable kind of gasket and much more prone to blow outs than other materials. Luckily, these are longer used so if you have a newer car this won’t be an issue.
How Do You Blow a Head Gasket?
The reason we use the term “blown” to describe what happens to a head gasket is very telling Because you need to maintain compression in the cylinder, over time that pressure combined with heat can damage the head gasket. The pressure can physically break the gasket causing a blowout. That's just one of several potential causes though, so let’s look at some of the others.
- Some gaskets can simply wear out due to extensive age. This is most common with composite but could happen with multi-layer steel as well.
- Incorrect gasket installation is another potential cause for the gasket to blow. This can be because the gasket is the wrong size and not meant for your car, or it was just installed incorrectly.
- Extremely high engine temperatures can cause the gasket to blow. Something like a coolant leak makes the engine run hot and the gasket is unable to maintain a seal in such high heat, breaking or warping as a result of expansion in the heat. High temperatures may be the most common cause of blown head gaskets.
- Hot spots are a problem in some engines that result in blown gaskets and these can be harder to predict. Some engines are designed to have a very specific head gasket in place that actually fills certain spots on the cylinder head. Replacing the factory gasket may expose hot spots that aren’t protected any longer and will wear out the new gasket faster.
- Abnormal combustion may also cause a head gasket to blow. If there’s an issue with your fuel injection or some other engine misfire problems, the mistimed ignition can put undue stress on your head gasket. This will weaken it over time and cause it to blow out sooner rather than later.
Needless to say, there are a variety of causes for a blown head gasket. Each one can have an effect on how to best repair the problem and what your final cost will be. Naturally, the kind of gasket will also figure into the repair cost as well.
How Can I Tell If I Blew a Head Gasket?
You know that you don’t want to blow a head gasket and that it’s going to cost a lot to fix, but how do you know it happened in the first place? There are a few things you need to be on the lookout for that could indicate a blown head gasket.
- White smoke coming from your exhaust may indicate you’re burning coolant and is a potential sign of a blown head gasket. Blue smoke caused by burning oil could also indicate the same thing.
- If the temperature of your engine is consistently high every time you drive, that’s a good sign that you may have a blown head gasket and should have a mechanic take a look.
- Look for any external coolant leak below the exhaust manifold.
- If your oil becomes milky or frothy it may be a sign that it has become contaminated thanks to a blown gasket.
- Consistent cylinder misfires are often the result of a blown head gasket. The lack of proper compression throws off the firing.
- Check your coolant for contamination. If oil has gotten into it there will be a film on top that is reminiscent of mayonnaise.
If you notice any one of these signs, or especially several of them, you may have an issue with a blown head gasket. Each of these issues is clearly something worth getting properly diagnosed so you should definitely be heading to see your mechanic as soon as you can.
Is it Worth Repairing a Blown Head Gasket?
In a word, yes. You cannot ignore a blown head gasket and expect to keep your car running in good condition. If a blown head gasket is not repaired in a timely fashion you risk a cascade effect of damage. That can result in damage to your ignition system, the fuel injection system, the exhaust system, and potentially even an entire engine repair or replacement. At that point, depending on the age and condition of the rest of your vehicle, this may make your car a total loss that’s no longer worth fixing. So for the potential $1,000 to $2,000 to fix the gasket, you could be saving the entire cost of a new vehicle that you may end up paying if you don’t address this issue as soon as you can.
With this in mind, you need to consider the value of your car as a whole. If you have an older vehicle, is it worth it to invest $2,000 or more into fixing it? If not, you may want to consider cutting your losses, selling the car as a junker and upgrading to something a little more reliable. It really all depends on the age and value of the car you have and how much time and effort you want to invest in it.
Why Does it Cost So Much To Repair a Blown Head Gasket?
The head gasket itself is not an expensive part and you can find them for $20 to $50 or so online. But that’s not what you're paying for when you get a blown gasket repaired. You’re paying for the labor and this is a labor intensive job. To repair a blown head gasket the engine needs to be pulled apart. This repair job can actually take a few days to perform depending on how busy your mechanic is.
This is a highly involved repair and it must be done with careful precision or the situation could actually become worse. While disassembling the engine will take time, reassembling it will take even more time. The cylinders only work when they are precisely timed to fire in order and calibrating them is not something you can guess at. This is an involved repair and it takes up the bulk of that cost you’re paying to fix a blown head gasket.
Repairing a blown head gasket is one of the most expensive fixes any car can ever face, up there with a total engine repair or a broken transmission. There are legitimately only three or four other repairs that may get more expensive, so you really do want to take this issue seriously if you don’t want to spend any more money than is entirely necessary.
Can I Prevent a Blown Head Gasket?
As you might expect there are things you can do to prevent a blown head gasket so that you don’t need to deal with the cost down the line.
- Keep an eye on engine temperatures. If you find your car running into the red on the temperature gauge too often, get it looked at right away. The longer your car runs hot, the more likely it will be that you will blow a head gasket.
- Pay attention to both oil and coolant in your car. Your owner’s manual will tell you exactly what kind of oil and coolant you should use, so make sure you follow the directions and get the right kind for your car. This will extend the life of all your internal parts and keeping a close eye on leaves can help you diagnose leaks.
- If your car is having engine misfires, have the problem diagnosed and fixed as soon as you can. Misfires can wear down a head gasket much faster than normal wear and tear.
- Do not miss those recommended oil changes! Many drivers let this slide for a very long time but there is a reason your manual will recommend an oil change after a certain number of miles. Follow it as closely as you can to extend the life of all the parts of your engine, including the head gasket.
Can I Still Drive with a Blown Head Gasket?
If your car starts after you’ve blown the head gasket, and that’s a big if, you really shouldn't try to keep driving unless you’re literally on the way to the mechanic. It can be very damaging to your engine to try to drive in this condition. The longer you drive the less likely it is that you’ll be able to continue to do so for long. Without the gasket in place you can get water in the engine, oil in the radiator, gasoline in your coolant, and so on. Essentially, you’re making a dangerous mess of your engine components. This can ruin your spark plugs, damage internal sensors, and more.
There is a product you can buy called head gasket sealer. This is a bottle of sodium silicate and other ingredients that are basically a kind of liquid glass with embedded fibres. When you pour this mix into your radiator and run it through your car for about a half hour, it bonds with your gasket to create a heat proof seal kind of like a bullet-proof vest. Reviews for the product on Autozone are generally favorable and indicate most people who use it have a lot of success improving the life of their head gaskets. It should be said that these are temporary fixes though and a liquid sealant will only last for so long. But it could definitely help you get a damaged car to the mechanic and even put it off for a few days if you absolutely can't afford to get to the mechanic to have the blown head gasket repaired just yet. The best part is that this product only costs about $13 so it’s clearly a cost-effective temporary fix.
In simple terms, you should avoid driving with a blown head gasket at all costs. If you absolutely must, a liquid gasket sealant mixture could help you get a little more life out of your gasket. Just remember, the longer you wait, the more costly this will get. That $1,000 could get to $2,000 and higher faster than you realize.