What Causes a Piston to Break? You need to know

You’ve probably heard of a broken piston if you’ve ever owned an old car.

It’s not a big deal, but you might have wondered: what causes a piston to break anyway? And what are cracked piston symptoms?

The piston is the part of an internal combustion engine responsible for converting the chemical energy of fuel into mechanical energy. It is also the engine’s part responsible for delivering the force required to power the engine.

When a piston fails, it is frequently due to an undiscovered minor manufacturing flaw, dirty piston, faulty rings or less engine oil. However, there are some cases where the parts can break for no reason.

This article will give you everything you need to know about cracked piston.

broken piston

What causes a piston to break?

A piston compresses air-fuel mixture in the engine to run the vehicle. It is used in many things, such as in the car’s engine, but it can break in some cases.

There are many reasons for a piston to break in an engine. Some common reasons are:

1. Dirty Fuel

People often break their pistons because they use dirty diesel or gasoline fuel. Using dirty diesel fuel can cause the engine to seize. When this happens, the engine becomes completely useless. It is a big problem for anyone who works with their diesel engines because they will likely stop working before getting back to your home or place of business. Clean the pistons if you notice carbon deposits.

2. Misfiring

Misfiring is also another reason why a piston may break. When the engine fails to fire, it can cause much damage to the engine and cause all internal parts to break. That is because the piston will be under a lot of pressure without being able to move. Misfiring is a serious problem and should be addressed as soon as possible.

3. Piston Rings

Piston rings are another part of your diesel engine that may cause your piston to break. The rings are used to keep the pressure in the cylinders of your engine, and they also help seal the cylinders by providing a seal between the cylinder walls and the piston. If one or more of these rings become worn, they will become loose, causing them to come out of place, which can cause to break. Regular inspections of rings are necessary to avoid this issue.

4. Tuning

If your engine is being tuned or adjusted, then there is a chance that the piston will break. You must have your engine tuned every once in a while to keep it running smoothly. If you do not tune and adjust your motor, the pistons could break over time and cause you much more damage.

5. Breakdown of the Timing Belt

A timing belt is a crucial component when it comes to keeping everything in sync. If the belt breaks, the two vehicles could collide, resulting in much more damage. To avoid it snapping, we must change the timing belt in accordance with the manufacturer’s recommendations.

Symptoms of piston damage:

Here are the most common symptoms of piston damage:

1. Differently colored exhaust smoke

Another indicator of piston damage is excessive white smoke coming out of the exhaust pipe. The air/fuel mixture burns too much oil when oil spills into the combustion chamber due to faulty pistons; the air/fuel mixture burns too much oil. Smoke that appears gray or blue and smells like burning oil is emitted from the exhaust pipe due to the extra combustion process.

2. Engine Noises

Piston slap is another name for the squealing noises made by an engine when a engine is damaged. Slapping occurs when the outer cylinder wall comes into contact with the vehicle’s inner wall. Friction between the surfaces is also increased due to the redesigned piston. Besides the cylinder, the rods connecting to it are also affected.

3. A Reduction Compression

Compression is reduced when the piston and cylinder are cracked, allowing more air to penetrate the two parts. The piston is inflated and lubricated due to the air and oil blown out of it. A cylinder leak-down test is needed to validate the cylinder cracks.

4. Engine Power Reduction

Another sign of piston damage is if the engine doesn’t work as well as it used to. We seal the cylinder walls and pistons to prevent leaks. In the event of a break or leak in the vehicle, it could alter the form and compromise the tight seal between the cylinder and the piston itself. Changing the design of a engine can cause it to lose effectiveness due to increased friction or oil seeping into it. It has a sluggish acceleration and a weaker pickup.

5. Oil Consumption Increases

Overheating and high oil consumption are both signs of damaged engine pistons. Because of a cracked or damaged piston, oil might leak into the combustion chamber and cause a fire. Engine parts that aren’t adequately lubricated are also affected by the leakage. It causes a buildup of friction and a decrease in the amount of oil. Symptoms such as low oil level dashboard alerts and vehicle overheating are prevalent.

How to prevent piston damage failure?

The following steps can help you prevent piston damage failure:

  1. Use high-quality lubricating oils, especially in piston and cylinder walls.
  2. Do not over-tighten the bolts after installing the pistons and cylinder kits.
  3. Inspect the pistons to make sure they are not damaged or cracked before installing them into the engine block.
  4. Make sure that all parts are installed correctly before you start your engine for the first time after installing a cylinder.
  5. Change the oil and filter regularly to maintain the lubrication of the engine.
  6. Keep the engine cool by using a fan as a cooling system or air conditioner for heat removal.


1. What happens if a piston is blown?

If a piston is blown, the engine will not start, and the resulting damage to the engine will be worse. If the piston is still inside the cylinder, it can be removed with a suitable tool. Once removed, you should inspect the damaged piston for any signs of leakage or cracking.

damaged piston

2. Can a broken piston be fixed?

Yes, if the damage is minor and the cylinder head is not damaged. If the engine has been running for some time, it is more likely to have to be rebuilt.

3. What causes the piston skirt to break?

The piston skirt damage can be happened due to manufacturing fault, low coolant level or wrong assembly during repairing. It provides a seal between the piston and cylinder head. If it breaks, it can cause leaks in the cooling or lubrication system and make the engine run rough.

4. What does a blown piston cost to repair?

The cost of repairing a blown piston might range from $100 to $200 per hour. Your technician will charge you for his time and materials and the cost of a new ring, which will bring the total to roughly $100.

5. Can you drive a car with damaged pistons?

Yes, in addition to engine oil consumption, exhaust gas pollution can also reduce your power output. Make a point of cleaning up your workspace. Piston Rings may wear out over time, but eventually, you’ll need to fix them.

6. Are pistons expensive to replace?

According to the automobile type and labor expenses, replacing a piston set might cost anywhere from $150 to $500. The cost of piston rings ranges from $40 to $100, depending on the number of cylinders in your vehicle. Between $100 to $400 is spent on labor.


Pistons are a vital part of your car, but they can also be costly. When pistons fail, it can cause your engine to overheat and even explode, which is dangerous. A piston will typically break when exposed to too much heat and pressure, and when it gets too hot, it expands, causing cracks to form and eventually break. Piston failure can be caused by several things, including a bad spark plug, oil starvation, or a dirty air filter. Hope now you have a clear concept about what causes a piston to break.


Mr. Rubel is an Engine Mechanic. He has more than 15 years’ experience on repair and maintenance of different kinds of vehicles. He is also providing training to mechanics and works as a Senior Mechanic of a well-known organization. He is sharing his knowledge to support the car lovers to solve the vehicle issues.

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