The cost of cylinder head replacement and labor costs can be expensive or minimal depending on various factors like the model and make of the car. However, the cost of labor can differ among mechanics. The cylinder head is a vital part of your car engine and is affixed to the engine block’s upper chamber. It has a valvetrain and specializes in sealing the combustion chamber properly.
A cracked cylinder head will greatly affect the performance of your car engine. Also, you’d notice frequent misfires, leaking coolant, or oil leakage. However, it’s important to take your engine to a workshop for diagnosis if you notice any malfunction or sudden breakdown.
Furthermore, the cost of cylinder head replacement varies depending on the type of cylinder. Aluminium-made cylinder heads are cheaper to fix than iron-made cylinders. The model and type of car also determine the price for replacing the cylinder head. Thus, this article will show you the symptoms of a cracked cylinder head and the cost of cylinder head replacement to help you make an informed decision.
- What is a cylinder head?
- Types of a cylinder head
- Why cylinder head cracks
- Symptoms of cracked cylinder
- How to replace a cracked cylinder head
- When to replace the cylinder head
- Cost of cylinder head replacement
- Final word
What Is A Cylinder Head
A cylinder head is found at the uppermost part of the engine, where it rests on the engine block. It comprises the intake and exhaust valves in charge of airflow. These valves take in the fresh air and serve as a gateway for the air-fuel mixture to escape from the combustion chamber. A cylinder head is also a covering for sealing off the combustion chamber.
Furthermore, a cylinder head plays a vital role in the smooth functioning of your engine. It contains several tracks inside, which help the air-fuel mixture travel freely to the valves. Also aids in the distribution of fuel.
Types Of A Cylinder Head
1. Flathead Cylinder Head
The flathead cylinder head is the first kind of cylinder head invented. This type of cylinder head is cheap and made of cast iron. It’s designed to secure the engine block and has no moving parts. It works best in compact engines because it’s a lightweight cylinder head.
Again, it performed poorly because it has coolant difficulties and doesn’t allow for a free movement of air. And also, the valves weren’t well positioned, which led to poor compression and combustion.
This type of cylinder head had many faults, making some car owners avoid them. However, small tractors, lawnmowers, and other automobiles with small engines made use of it.
2. Overhead Valve Cylinder Head
This cylinder head has been prominent over the years. They’re the improved version of the flathead cylinder head, making it preferable to the flathead cylinder head.
It contains spark plugs, tracks for intake and exhaust gases, and the valve train which helps the engine to perform at an optimum level. Also, this type of cylinder head doesn’t heat up fast.
3. Overhead Camshaft (OHC) Cylinder Head
This is the latest invention of cylinder heads, which houses the camshaft inside it, which is positioned in different forms. It can either be in the middle, on the valves, or between them. The overhead camshaft cylinder head also contains the spark plugs, intake, and exhaust valve. They’re configured singularly or dually.
The camshaft handles the intake and exhaust pipes in the single overhead camshaft cylinder head. At the same time, the dual overhead camshaft cylinder head has two different camshafts made specifically for the two valves.
Furthermore, the single overhead camshaft cylinder (SOHC) is more cost-effective in production than the dual overhead camshaft cylinder (DOHC) head. This type of cylinder head allows the free flow of air, moves at high speed, and gives better engine performance.
A well-designed cylinder head will last long because most newly manufactured cars have cylinder heads built with aluminum. While older vehicles have iron-made cylinder heads in them. The cylinder head will crack due to extreme temperature and pressure inside the cylinder, which produces an uncomfortable environment for the cylinder head.
Over time the materials will begin to weaken, and the head will crack in single or multiple places. Additionally, your cylinder head will crack under the following circumstances.
Cost Of Cylinder Head Replacement, Causes Of Cracks #1: Excessive Heat
A major cause of cylinder head crack is excessive heating of the internal combustion engine. During combustion, much energy is incidentally converted to thermal energy against kinetic energy, which powers the vehicle. However, so much heat is produced as a result of that, and an overheated engine will stretch its components beyond what they can contain, and therefore cracks will happen.
Note that most of the cylinder heads are manufactured with aluminum and may crack when the engine overheats.
Cost Of Cylinder Head Replacement, Causes Of Cracks #2: Bad Thermostat
The engine operates at a high temperature (190° to 200°F or 89° to 99°C) to function maximally. But if the temperature decreases it will increase fuel consumption or there’ll be an occurrence of emissions. However, if the engine overheats, it becomes unbearable, and the head may crack. That’s why it has a thermostat that controls the heat level of the engine.
It works to prevent the coolant from cooling down the engine when it hasn’t reached the ideal temperature for normal functioning. And it opens up again to allow the coolant to cool down the engine to room temperature to avoid overheating. This cycle goes on and on while the engine operates.
However, if your thermostat is bad or has failed to function and refuses to close, it’ll remain open, which will cause the coolant to circulate throughout the entire engine and cool it down. Once the engine is unfit to warm up, it becomes a problem.
Likewise, a closed thermostat is even more dangerous because the engine will overheat without being cooled down by a coolant (as is the case when you notice a P0128 code in your Jeep or a P0128 Dodge code). The coolant will also become very hot, which will crack your cylinder head.
Cost Of Cylinder Head Replacement, Causes Of Cracks #3: A Poorly Designed Cylinder Head
A cylinder head that isn’t designed well or designed with inferior materials will not be able to withstand little discomfort and thus will crack easily. That is why a new engine may be experiencing cracked cylinder head issues.
Cost Of Cylinder Head Replacement, Causes Of Cracks #4: Defected Water Pump
A defective water pump will cause improper circulation of coolant in the entire engine. The coolant in the radiator may be cold, while the coolant around the cylinder head and the engine block will have insufficient coolant because of the bad water pump (you can find out more about how it works in our explainer on what is the water pump in a car and what does the water pump do in a car).
That is because the water pump makes transporting water and coolant faster and easier. But a defective water pump will result in the manual circulation of coolant, which is very slow and will take so much time to cool the system before overheating sets in. And in many cases, the engine always overheated.
Cost Of Cylinder Head Replacement, Causes Of Cracks #5: Excessive Emissions Or Poor Power
If you’ve changed your emissions system or horsepower, you may likely experience cracked cylinder head problems. Because you may have affected your engine timing. For example, deleting emissions control systems can create an environment that makes the cylinder head more susceptible to cracking, especially when installing twin turbos.
Also, engines with deleted emissions control systems (to learn more about the side-effects, check out our guide on do all cars have a catalytic converter) may crack their cylinder heads from higher compression ratio piston, timing, and air-and-fuel ratios that are out of balance. Note such emissions systems deletions are illegal and should not be practiced.
Cost Of Cylinder Head Replacement, Causes Of Cracks #6: Overtightened Bolts
If the bolts holding the cylinder heads and the engine blocks are over-tightened, the cylinder head becomes too overwrought and cracks. Also, it can be stressed out by the constant explosions inside the engine, which heats it and may result in a crack. However, this is not a major occurrence.
Cost Of Cylinder Head Replacement, Causes Of Cracks #7: A Frozen Engine
If you reside in an extreme weather location and are experiencing a cracked head, you may want to check if the coolant is frozen. Because if the coolant becomes too light, it may not be able to warm up the engine, so the water freezes. Over time the frozen water will expand in the engine pushing forward, resulting in cracks on your cylinder head. However, note that this mostly occurs during harsh cold weather conditions.
Cost Of Cylinder Head Replacement, Causes Of Cracks #8: Coolant Leak
A faulty cooling system will result in overheating and thus, cause cracks on your cylinder head. Because when excess coolant leaks out, over time, there’ll be little or none left to cool down your engine. Overheating may occur, which will cause the engine to experience a high pressure beyond what it is designed to handle, and thus, cylinder heads will begin to crack.
Symptoms Of Cracked Cylinder Head
When your car is exhibiting some symptoms, it could result from a cracked cylinder head. But the symptoms of a cracked cylinder head and a blown head gasket are alike. The following symptoms below are a red alert for a cracked cylinder head.
1. Emission Of White Smoke
When there’s an emission of white smoke from the exhaust pipe, there’s a possibility of a cracked head. When there’s a crack in the cylinder head, the coolant leaks into the combustion chamber, which in turn causes emission of white smoke from the engine.
Also, if an oil leakage comes in contact with very hot engine parts, this will cause the emission of smoke from the exhaust system. Again if the cylinder head is not properly sealed, exhaust gases can exit from it through the exhaust valve before getting to the manifold.
2. Illumination Of Warning Lights
When there’s an illumination of the warning lights on your car dashboard, this might indicate a cracked cylinder head. These warning lights are the check engine light, engine over-temperature light, low coolant level light, and other indicator lights in your car.
3. Mixture Of Coolant With Oil
Coolant and oil mixture is a sign of a cracked cylinder head. Although this is also a symptom of a blown head gasket. However, this problem can make the combustion gases enter the coolant which may be confused for an oil mixture. Either way, note that the coolant and oil mixture is the only sign of a cracked head.
4. Impoverished Engine Performance
The speed and overall performance of the engine will drop because of a cracked cylinder head. Engines perform excellently when all the components are in good condition. Once a cylinder head is cracked, there’ll be a loss of compression which will badly affect the engine’s performance.
5. Overheating Of The Engine
Engine overheating will occur when your car’s coolant level is very low and thus will not be able to cool down the engine properly. The temperature gauge and the engine overheat warning light will begin to indicate excess temperatures in the engine. An overheated engine should not be driven again, or you’d incur more damage to your car.
6. Poor Coolant Level
It’s no new thing that a crack in your cylinder head will release coolant into the combustion chamber. Thereby reducing the level of coolant in your cooling system. The more the reduction of coolant level in your cooling system the more cracks your cylinder head will experience.
7. Engine Misfiring
A cracked cylinder head will cause your engine to misfire. Because the mixture in the combustion chamber will not burn appropriately, causing your engine to misfire. Low engine compression can also cause a misfire. Overall, a cracked cylinder head will affect your engine’s smooth running, which may die while driving and you’d have to restart again.
8. Presence Of Combustion Gases In The Coolant
Combustion gases can escape into the cooling system if the cylinder head is cracked. That will put the cooling system in a highly pressured state and there might also be a lot of bubbles in the coolant before boiling occurs. So these signs indicate a cracked cylinder head.
9. Oil leakage
The oil in your cylinder head will likely leak out once a crack occurs. If you notice an oil puddle under your car, this might be an indication of a cracked cylinder head. Or if the oil level warning light on your dashboard illuminates it, it indicates a low oil level which can also result from a cracked head. So, make sure you know how often should you check the engine oil level.
10. Coolant Leakage
Coolant leakage is one of the causes of a cracked head and a symptom of a cracked cylinder head. If you notice some leaking coolant, your cylinder head has an intense crack.
The consequence is overheating the engine, which is dangerous for your car. Coolant leaks can happen internally; however, once your indicator light on the dashboard illuminates, pause and examine the coolant level.
How To Replace A Cracked Cylinder Head
Replacing the cylinder takes some hours to complete. Say five to six hours, and it’s a process you must follow adequately to replace it properly.
- First, you’d need to drain the coolant and oil mixture.
- Then unmount the intake and exhaust valves.
- Next, remove all the timing chains or belts.
- Remove the cracked cylinder head.
If you have a double cylinder head, you may need to remove both and replace them if the problem requires it. Removing and replacing a cracked cylinder head with a new one is a very difficult job that requires the help of a professional. Of course, it’ll cost you a fortune to achieve.
When To Replace The Cylinder Head
The cylinder head is one of your car parts designed to last a lifetime, depending on how long your car lasts. However, it’s necessary to maintain your car regularly to be in its best condition. Ensure a regular oil check and changes where necessary. Once your cooling system is faulty, fix it immediately. Don’t drive an overheated engine to avoid further damage.
But if your cylinder head cracks, send it for a replacement immediately for your car to be in good working condition. Failure to replace your cylinder head immediately will give rise to more severe problems (like acquiring a new engine), which will incur more expenses.
Cylinder Head Replacement Cost
The cost of cylinder head replacement differs depending on the model and type of car. And this will involve the cost of labor and mechanic repair costs.
Furthermore, cylinder repair and replacement most time are done by expert mechanics because this whole process is a complex type. It requires dismantling a large part of your engine. But you can also do it through DIY techniques.
However, before you resought a DIY cylinder head replacement, ensure you have the needed parts, expert knowledge, and experience in car repair. Both methods differ, but the mechanic workshop services are costlier than the DIY technique.
The cost of cylinder head replacement without tax and fees, irrespective of your car type, is estimated to be between $3,400 and $3,750. The labour costs about $1,190 and $ 1,510. Labour takes about five to six hours to complete the replacement. The cylinder head replacement costs around $2,210 and $2,240. Note that this cost estimate is what you’re likely to pay at an auto repair shop.
For a DIY, the cost of cylinder head replacement is around $2,210 to $2,240. Ensure to have these tools before embarking on a DIY method.
- You’d need a new cylinder head for replacement.
- A wrench set, socket set, a ratchet set, and screwdrivers.
- New engine oil and coolant.
Cylinder Head Repair Cost
A cracked cylinder head costs about $200 to $500 to purchase the parts. With a labor cost of about $80 to $100 per hour also, depending on the model and make of the car. This cost summary applies to aluminum-made cylinder heads, and this is what most cars make use of.
Audi, BMW cars, and some others require removing some parts before removing the cylinder head. And this may take a couple of hours, thereby increasing the labor cost per hour.
Additionally, due to their boxer engine design, Subaru cylinder heads take longer to remove. The cost of a cracked cylinder head replacement for Subarus is over $1000.
Cost Of Cylinder Head Replacement: Final Words…
The cost of cylinder head replacement is a guide to help you know how much to set aside for a total replacement. If your cylinder head is severely cracked, you may need a total replacement, but if you have minor cracks, you may opt for a repair. However, the cost of replacement and repair for a cracked head has a wide margin. This article has discussed both to help you make an informed decision.
FAQs On Cost Of Cylinder Head Replacement
What Is A Head Gasket
The head gasket is a seal between the engine block and the cylinder head to prevent pressure loss and engine fluid leakage.
What Causes A Blown Head Gasket
Several factors are the causes of a blown head gasket. First is overheating the engine, pre-ignition and detonation, wrong installation, extremely high and too low temperature, aging, and high mileage.
How Much Does It Cost To Replace A Head Gasket
The national average cost estimation is between $1,624 and $1,979 for a head gasket replacement. The labor costs are estimated between $909 and $1147, and the parts are about $715 and $832.
How To Fix A Blown Head Gasket
Keep your vehicle manual close by for guidelines. Mount your vehicle on a lift, wear eye goggles and wear a hand glove. First, drain the coolant and oil mixture, and a battery disconnection follows to take out the fan shroud in front of the engine. Remove the radiator and safely keep the screw, nuts, and bolts. Remove the plenum chamber, the belts, the pulleys, and the water pumps. Unscrew the conditioning compressor, unfasten the spark plugs, and remove all the hoses and wires out of the way. Clean up any component drained with oil or dirt, and carefully remove the heavy intake manifold and cylinder head. Remove and inspect the head gasket alongside the engine block. Clean the cylinder head and cylinder walls. Put the new head gasket in the right order and fix and tighten all the components removed.
Where Is The Head Gasket Located
It is located between the cylinder head and the engine block.
What Does A Head Gasket Do
The major role of a head gasket is to seal the combustion chamber to maintain adequate compression levels, prevent coolant leaks, and prevent engine overheating.
How To Know If Head Gasket Is Blown
If you notice any of these signs, it indicates a blown head gasket. Engine misfiring, coolant and oil leak, white smoke from the exhaust, engine overheating. These signs are some of the major signs.
How Do You Know If Your Engine Is Blown
You’d notice a blue-colored smoke from the tailpipe. That indicates the presence of engine oil in the combustion chamber. Rattling noise from the engine, presence of coolant in the engine oil.
What Causes Engine Block To Crack
The major cause of engine block cracking is overheating of the engine. When the engine overheats, it experiences thermal stress, and the engine block gets cracked. Extreme cold weather conditions can also cause engine block crack. Here the coolant gets frozen and expands the engine, causing cracks on the engine block.