Engines. If you love your car, you must also love its engine, because without it your vehicle will go nowhere. Inside that engine, you’ll find a host of individual parts and components that work together in perfect harmony so that when you press the gas pedal, the vehicle moves. That’s fine, as long as all the parts and components are happy and working together. However, when they start to fail, you can see this in reduced engine performance and maybe even complete failure.
Nobody wants that, so in this article we are going to take a look at one of the most vulnerable parts of the engine, the brave little cylinder heads. We will look at the symptoms you will notice if your own cylinder heads are cracked and then we will assess the cost you are likely to face to repair them.
What is a cylinder head? head cracks
The cylinder head is a key component within an internal combustion engine. So if you’re driving an electric vehicle, congratulations, you don’t have cylinder heads to break. However, for most of us who drive traditional gasoline cars, we rely on cylinder heads to help power our vehicles. So what are they?
Well, inside the engine block of an internal combustion engine there are cylinders. It is within these cylinders where gas and air mix and cause combustion. This combustion forces the vehicle’s drive chain to move (via pistons) which in turn transfer energy to the car’s drive wheels. The short version of that? Small controlled explosions in tubes move the vehicle forward (or backward).
What about the cylinder heads? cracked cylinder head
The cylinder heads are located, as the name suggests, at the top of the cylinder. The heads close the cylinder and contain the air-gas mixture plus the combustion effect. They are then opened to vent the exhaust gases. They do this thousands of times a minute and each time they close they create a pressure seal inside the cylinder. Each time they are opened, they are enveloped in hot gases.
That’s a pretty tough life, so the cylinder heads are made of sturdy materials. In older cars, they are often made of iron, for example, while modern cars will opt for aluminum as the material of choice.
So what is the problem? cracked engine head
The problem is, while they are made of sturdy metal, they also have to be quite light. If the cylinder were too heavy, it would not be able to complete its arc of motion within the cylinder fast enough. That would mean that the engine would be less efficient.
For vehicle manufacturers, this is a careful balancing act. For one thing, the cylinder head must be strong enough to last for years of service; no one wants to disassemble and replace their heads every six months. On the other hand, it must be light enough to perform its function without affecting the performance of the engine.
Sounds like a hard gig: cylinder head
It is, but vehicle manufacturers have practically learned the formula. Generally speaking, an aluminum cylinder head will give you around five years of useful life. An iron one can sometimes last a little longer, say six or even seven years. After that time, all cylinder heads will be in danger of cracking. Fortunately, there are a number of symptoms you can look for that indicate a cracked cylinder head. Symptoms to look out for include:
Symptoms of a cracked cylinder head: engine head repair
It is not strictly a symptom, but something to be aware of. If your vehicle is new and two or three years old, it is unlikely that any engine problem is related to a cracked cylinder head. Note that we said unlikely, not impossible.
2. Oil leaks; cost of repair of engine heads
The cylinder head contains oil. This serves both to lubricate your movement and to help dissipate heat. Both very useful functions, so thank you oil! However, as perhaps expected when something cracks, a cracked cylinder head will start to lose that oil quite quickly. There are a couple of ways this symptom could present itself. First, you may notice an oil stain that has built up under the engine when you have the vehicle parked in one position for a period of time. Second, in a modern car at least, the “Check Oil” check engine light may appear on the dash display.
3. Refrigerant leak; head crack