The cost of repairing the head gasket is primarily labor costs, as parts are cheap. Replacing a head gasket could take anywhere from 6 hours to a few days. Looking at average out-of-pocket costs between $1,000 to $3,000, it may be best to consider scrapping the vehicle instead.
If you are anything like me, when you even hear the words ‘changing a blown head gasket,’ there is a high probability that even the calmest person in the world may cease to be calm during the thought of that experience.
However, in this article, we will discuss everything that you need to know about this expensive repair, whether it is worth paying for, and how much it costs to fix a blown head gasket.
What is a Head Gasket?
A head gasket provides a seal in connecting an engine block to the cylinder head. This seal allows oil and coolant to move between the engine block and the cylinder head to provide lubrication to the engine and to also keep the engine within a safe temperature range.
A head gasket also provides a seal for the combustion chamber in which the spark plug generates pressure that must remain in the combustion chamber while the engine is running. If enough lubricant and enough coolant are not present, the engine can either seize or overheat, which can result in major challenges.
Moreover, if there is not enough fuel pressure from the combustion to push the pistons, the engine will not have any conceivable power to operate.
As you can see, the head gasket is a significant component of the operation of your engine. When the head gasket fails to perform its necessary function, it is considered “blown,” in that you will need a new head gasket.
The primary reason that blown head gasket repairs are so expensive is that it is difficult to get to, making this not only a time-consuming replacement, but also a difficult one.
Unlike changing an oil filter or spark plug, both are easily accessed. To get to the head gasket, you will basically strip a majority of the engine.
The knowledgeable and essential part of replacing a head gasket is to address the issue at or first sign of an issue. Ignoring the issue may lead to more damaging impacts, like a cracked engine block or a warped head.
Both of which can be caused by the engine getting too hot due to insufficient coolant, which is usually caused by a leak.
What are head gaskets made from?
There are many options to discover, However, the head gasket itself is rarely going to exceed $350, and more often than not, your vehicle will be more expensive to fix once a blown head gasket has occurred.
Let’s take a look:
Graphite
Graphite gaskets not only dissipate heat well so that burnout cannot occur, but they are also cheaper, which lowers the total cost of replacing a gasket. They can handle extreme heat, which helps mitigate brining and make them less susceptible to creep.
Another reason graphite head gaskets seal better than other materials is the level of compressibility. This type of gasket works best if the head and block are composed of different materials, like an aluminum head on an iron block.
Composite
Composite gaskets for head gaskets are mostly discontinued, however, they have a purpose. If you are dealing with mods, composite gaskets are easy to trim, are a reliable option.
Composite gaskets are primarily made of graphite and asbestos, they are made of materials that are resistant to coolant, gas, oil, and alcohol. The drawback is also the reason they are somewhat less popular, due to the abundance of asbestos, which is toxic.
Rubber
Rubber head gaskets have become widely used because they are easier to install than most options. Rubber gaskets perform well resisting heat, and flexibility makes them great at not leaking.
A rubber head gasket would be a good fit if you were trying to keep the price down with a blown head gasket.
Cork
Cork gaskets compress easily, which helps provide a good seal, and they handle high temperature and high vacuum situations well.
The downside to cork gaskets is that they dry out and become brittle, which makes them much easier to crack or crumble. They also have the drawback of being likely to tear and leave behind a residue when removed.
Copper
Copper head gaskets are more expensive, but they are worth it if you have a high-performance vehicle, and thus will add more value. Copper distributes heat evenly, which controls warping, and many aftermarket parts generate heat.
They have the plus of being malleable and conforming to nearly any surface no matter how rough, which provides a good seal.
Multi-Layered Steel (MLS)
MLS head gaskets are becoming the number 1 choice for vehicles today. MLS head gaskets are made of thin layers of metal coated so that they also conform to the surface of the block and head.
MLS gaskets can nearly avoid distortion altogether when made correctly, making them the head gasket of choice for supercharged or turbocharged models. While they are slightly more expensive, they hold up well under constant pressure and usually last a long time.
Some other options exist to mention:
- Dead-soft aluminium
- Carbon
- Fiberglass
Now you have a better grasp of what a head gasket is made from, and look at costs, let’s discuss what can lead to needing to replace a head gasket.
Causes of a Blown Head Gasket
The job of head gaskets is to seal the connection between the engine block and cylinder head. Allow fluids, such as oil and coolant, to run through, without leaking out.
When it cannot seal, it is called “blown,” and you’ll need to start the process of obtaining a head gasket repair estimate. If not, you’re headed for worse problems, like a cracked engine block or warped cylinder head.
There are many causes of a failed head gasket, including defective parts, and regular wear and tear. Nothing lasts forever, including a head gasket. The good news is that most of them last at least ten years, as much as you look after the cooling system, and check for its good condition.
It is more common in performance vehicles, due to overworking the engine past its limits. A copper or MLS head gasket will minimize the chances of a blown head gasket.
How will you know when you have a blown head gasket? Often it could be a loss of power due to the escape of pressure from the seal. More than likely, you will experience overheating. This can happen in cases when exhaust gases enter the cooling system instead of the tailpipe.
Another option is coolant entering the combustion chambers, causing a phenomenon called Hydro Lock. In that case, it is possible the engine will seize, and affordable repairs will be the least of your worries.
Does white smoke mean a blown head gasket? Good question. Maybe yes. It happens when anti-freeze escapes through a malfunctioning head gasket and enters the combustion chamber. This creates thick, “sweet-smelling,” white smoke as it burns off.
As explained above, replacing a blown head gasket as soon as you can is a necessity to prevent further damage.
Other symptoms include:
- External coolant leak
- Fouled spark plugs
- White smoke from the exhaust
- Overheating
- Bubbles in the radiator
- White, “milky” oil
The main cause of a head gasket blown, is engine overheating by extreme temperatures. It can be caused for a number of reasons. For example, adding performance parts, that may push it past its limits.
But it can just be crushed and damaged, due to the movement between the engine block and cylinder head. It is also most possible you have a failure with a different component of your engine.
Like the cooling system. If the water pump fails, there will then be inadequate circulation and engine failure, leading to a blown head gasket.
System failure also include:
- Badly designed head gasket.
- Pre-ignition.
- Hot spots.
- Wrongly installed.
However, it was broken and blown – it was. Do yourself a favour and replace it before it blown major problems.
Now, let’s look at how you test for a blown head gasket.
Can You Test for a Blown Head Gasket?
Fortunately, you won’t always have to either take your car to the shop or wait until the problems get worse to find out whether you’ve blown a head gasket.
Let’s take a look at some simple ways to test if you need gasket repair:
Remove the Oil Cap
You can look and see if any coolant has somehow leaked into the oil by looking inside the oil filler cover. To reveal the inside, wait for the engine to cool after it was running and take off the cap. If you see a milky brown substance on the bottom you are leaking coolant somewhere.
This is not a specific way to determine you have a blown head gasket, but it does indicate you have a significant issue. A small amount of moisture is completely normal.
Check for Fluid in Combustion Chamber
As I mentioned before, the head gasket is supposed to keep coolant where it belongs, within the engine block and cylinder head. When it begins to fail, it is possible that some of it leaks into the combustion chamber.
You can check for this by first completely removing all of the spark plugs then, you would run on your AC and crank the fan, and start the engine. Watch the holes where the spark plugs were, If you notice fluid (coolant) in any of the holes you have bad news, you have a blown head gasket.
Checking the Radiator For Bubbles
You might notice that there are a few indications of a failed head gasket, one of them being exhaust gasses going anywhere but out the tail pipe. One of the areas that exhaust gasses can go is in the cooling system.
You can check for exhaust gasses by checking for foamy bubbles after removing the radiator cap while the engine is cold. It is important that you do this while the engine is cold. If you did this when the engine is hot, you may release a hot pressurized burst of hot coolant.
The other methods for checking for a blown head gasket are a little more complicated and consist of a pressure test on the cylinders or a chemical test.
Either way, to use either process, you will either have to buy the supplies through online or internet option and most auto parts stores carry the products now. You will also be able to have a shop perform the tests for you, but expect to pay about $100 for each test.
Now that you have hopefully have a better idea of how to tell if a head gasket needs replacing. It is now time to review the average costs for head gasket repair.
How Much Does It Cost To Replace A Head Gasket?
For a high-performance valve cover gasket, the average replacement cost of gaskets is rarely more than $350. And let’s say you got lucky, and no further damages occurred before you were able to replace a blown head gasket.
Without factoring in labor, the average cost to replace a head gasket usually comes in under $100.
The number one item that is most costly when it comes to replacing a blown head gasket? Its most certainly the labor hours involved, anywhere from 6 hours to multiple days. Depending on the engine complexity, the labor costs can set you back anywhere from $1,000 to $2,000, and I’ve seen as high as $3,000.
Remember, to even get to the head gasket, nearly every major part has to come off and then also be put back together. Expect to pay more if you are working on a newer model with either a turbocharger or supercharger, versus an older car without these characteristics.
Would it be worth fixing a head gasket? That is an entirely personal decision for each person to make. A good way to break this down is if the blown head gasket fix would total more than the value of the car; it is not worth fixing.