Cylinder Head Cracks

Cylinder Head Cracks: Symptoms & Causes

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Every driver and the car owner can become curious about what causes cylinder head cracks and the symptoms to look out for when this happens. Although not many may be able to explain why a car engine’s cylinder head should crack, there are bothered with the solution. Seeking a way out of a cylinder head failure means that one has recognized a problem with the part, with certain signs and symptoms starting to show as you drive your car along. 

Everyone knows the vital part a cylinder head plays in a car combustion engine. Apart from sealing the engine’s combustion chamber, the cylinder head also serves as the case to house the valves for effective airflow. 

Its failure may cause a breakdown of the engine and by extension the vehicle. There are some symptoms to watch out for to be able to conclude that your vehicle’s cylinder head is faulty. If you’re not sure if there’s a crack in the cylinder head, this article will guide you through all need to know about this problem. You’ll also learn the causes of a failing cylinder top-end and the solution out of it.

What is a Cylinder Head Crack & How it Works? 

As earlier noted, an engine cylinder head features within a car’s internal combustion engine. It works with the head gasket and engine block to cause a closure to the combustion chamber of the engine. Without a functional cylinder head, the combustion chamber – where the engine burns to give power to the car- won’t work. 

Besides, a cylinder head also encases both the intake and exhaust valves to ensure there’s direct airflow into and out of the engine, allowing the combustion chamber to exit the burnt air-fuel mixture. As a customized component of your vehicle, a cylinder head is designed to connect other parts of the engine, thanks to its milled surfaces. This effective mating will help provide a flush and smooth fit with other parts. 

In the event that the cylinder head cracks, the engine’s cylinder may start to misfire and so become unable to compress. 

Cylinder Head Cracks Symptoms

From our guide so far, the cylinder head shouldn’t be allowed to develop any fault, and if it cracks, ensure the fault doesn’t stay long before it is fixed. What signs should you look out for to be able to correctly diagnose that your cylinder head has cracked?

Let’s take a look. 

  • Engine not Idle

One of the foremost symptoms of a cracked cylinder head is a weak engine. Don’t forget the cylinder head serves to protect internal combustion, directing and containing all the processes in the combustion chamber. 

However, if the capacity to contain and direct combustion is weakened or hindered, the efficiency of your car engine diminishes, leading to failure to power the vehicle. Weak engine results in lethargic acceleration and lower gas mileage.

  • Oil Leakage

If you notice that the oil in the engine is leaking, there’s a chance that the cylinder head is leaking. The consequence of that is that most of the mechanical parts of the vehicle, including the cylinder head, will not be lubricated. A large volume of oil formed on the ground after you have parked the vehicle for a long period of time is a great sign that your vehicle cylinder head is failing.  

  • Misfiring engine 

Another sign to look for when there’s a cracked cylinder head is that your car engine will misfire. Combustion which requires a great atmosphere for the mixture of air and gas, will not take place properly as a result of an unsealed cylinder. The result is that the engine may fail to start, die repeatedly, or misfire.

  • Engine Smoke

A cracked cylinder head will result in smoke and gases coming out of the engine. This dangerous failure of the cylinder head causes the engine to produce a large amount of exhaust that goes back directly into it.  

  • Coolant Leakage

The engine receives fresh air to cool down after working for hours. However, the coolant may fail in its responsibility if the cylinder head is not working properly. When you notice a puddle of oil forming under the car after parking, you will need to check if the cylinder head has not cracked.

Common Causes of Cracked Cylinder

  • Overheating

A cylinder head may crack if there is a lot of heat generated due to internal combustion. When your car engine overheats, various other components, including the cylinder head, can be stressed beyond the heat-resistant capacity that they’re designed to hold out against. Some of the cylinder heads are made of aluminum materials and this causes them to be easily susceptible to crack or warp once the engine heats it up quickly.

  • Failed Thermostat

Engine temperature levels are meant to operate optimally: if it operates below standard temperature, it may lead to wear, emission, and fuel consumption; if it over-operates, it’ll cause over-heating. The thermostat allows coolant to supply ambient temperature to the engine; that’s why it needs to open; if it’s stuck closed, the engine will overheat and the cylinder head may crack due to too much heat.

  • Coolant Leak

Too much heat causes the cylinder head to crack and so leads the coolant to leak. This will cause engine malfunction. In reverse order, once there is too much leak of the coolant, the cylinder head will also start to fail.

Cracked Cylinder Head: Repair Cost

The cost you incur in fixing your car’s cracked cylinder head will depend on the materials the cylinder head is made of and the brand name of its manufacturers. You will also have to consider the make and model of your vehicle as well as the cost of parts and labor of the technician you will hire.

On average, you may have to prepare something in the region between $200 to $300 to buy parts. Labor cost may be around $500 at $100 per hour, depending on the state of residence and the extent of damage to the vehicle.

Final Thoughts 

Gas-powered vehicles rely solely on cylinder heads to come to life. Although owners of electric-powered vehicles don’t have to bother about this problem because they won’t have a cracked cylinder head, there is a need for caution. Regular checks and repairs are an essential aspect of driving.   

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