Is It Worth Repairing A Cracked Engine Block? An Ultimate Guide for Car Owner


When it comes to checking your car for any issues under the hood, very few repairs can drain your wallet more than a cracked engine block. A cracked engine block is so expensive and intensive to repair that you might be wondering if it’s a route worth taking.

So, if you recently received this diagnosis from a car repair service, this article shall help guide you on what to do next.

Is It Worth Repairing A Cracked Engine Block
Is It Worth Repairing A Cracked Engine Block

Engine Block: What Is It?

A car’s engine block is a cast iron or aluminum casting that acts as the engine’s bottom part. This block serves as a foundation for the car’s cylinder head and other major engine components.

In addition, the engine block houses other parts such as pistons, crankshaft, connecting rods, and even the camshaft in some cases.

The engine block and its internal components are often considered the ‘bottom end’ while the cylinder head and other related parts are referred to as the ‘top end’ of an engine.

Do All Cars Have An Engine Block?

No. Modern electric cars like Tesla cars don’t have engine blocks. This is because electric vehicles run on an electric motor powered by and charged with electricity.

Learn more about the time it takes to charge a Tesla here.

Traditional gas-powered cars have an internal combustion engine that’s powered by fuel. Thus, the engine you’d typically find in a fueled car is non-existent in an electric vehicle.

Also, the purpose of an engine block is to support the engine in a gas-powered car. Since an electric vehicle has no use for an engine, an engine block and other typical engine components are unnecessary. They’re not included in the design of an electric car.

How Does An Engine Block Crack?

In general, engine blocks are constructed from steel or iron and are built to last. So, how does an engine block crack?

Some parts of an engine block are thick, durable, and unlikely to crack. However, other components may be a lot thinner. The small passageways and cylinder walls in the block where the coolant flows are thinner and more prone to cracking.

Also, engine overheating is the most common culprit of a cracked engine block. The block may crack when your car engine gets too hot due to thermal stress. In contrast, engine blocks can also crack in freezing temperatures. If the cooling system doesn’t have enough antifreeze or is filled with too much water, the water may freeze and expand, causing cracks.

Furthermore, casting and design flaws may also result in cracked engine blocks. For instance, the 8th generation Honda Civic with model years from 2006 to 2009 is known to have engine block design flaws. These cars have casting flaws that cause the engine block to crack. Because of this, Honda provided an extended warranty to these cars to address the issue.

What Are The Signs Of A Cracked Engine Block?

The chances of a cracked engine block are rare. In general, the cylinder heads are the first to crack and start causing issues before the block does. However, there are still instances where the block can crack and cause the following symptoms:

  • Smoke or steam from exhaust pipes
  • Overheating engine
  • Oil or coolant leaks
  • Combustion gases in the cooling system
  • Misfiring and rough running
  • Illuminated warning lights
  • Coolant and oil intermix
Is It Worth Repairing A Cracked Engine Block

How To Fix a Cracked Engine Block?

As mentioned before, the block is the ‘bottom end’ of your car’s engine. So, everything needs to be stripped from the engine when you have to fix it. This means the engine is removed from the vehicle, and every part needs to be disassembled and removed.

Once stripped down to the bare engine block, it’s pressure tested to determine the engine’s viability and integrity for a repair. A machinist may insert repair plugs into the cracks in the best-case scenario or simply weld the crack. Some will require a block replacement. In the worst-case scenario, there’s nothing you can do about it.

If you get lucky and the engine block can be fixed, the process is still rigorous and will be quite expensive. You’ll need new seals, bearings, gaskets, other critical components, and routine service parts and fluids. There’s also a chance you have to fix or replace broken or damaged components during disassembly. You must also check that the cylinder head itself hasn’t been damaged. Otherwise, that alone is another project of its own.

Repairing An Engine Block: How Much Will It Cost?

Repairing an engine block can set you back over USD$1,500 in machining and parts costs from start to finish. You also need to worry about the labor cost. An engine block repair can go about 12-35 hours, depending on your car.

Truck and diesel engines are often harder to work on, while repairing smaller cars and standard models is less time-consuming. In general, the average car repair labor rate will cost you about USD$75-USD$130 per hour. Assuming the process will take about 20 hours, that’s about USD$1,500-USD$2,600 to repair a cracked engine block. But it could be so much more. 

Also, note that the repair cost will be different depending on where you get the job done. For instance, when getting the job done at a local dealership, you can expect to pay higher fees compared to smaller independent car repair shops.

Is It Worth It?

With such expense, you might be wondering if it’s even worth repairing your engine block. Well, it depends on your particular situation.

If your vehicle is only a few years old and in generally good shape, it’s probably worth spending the money on repairs. With a successful repair, it should give you more decades of use. But if it’s an older car that already has other issues, then your money is probably best spent purchasing a new vehicle instead.

If you realize that the repair costs for a cracked engine block and other significant issues are piling up and approaching 75% or more of your car’s value, it’s certainly not worth the repairs.

In addition, there are other things you need to consider when thinking if a repair is worth it. For instance, some people may get bored with their current vehicles. Thus, you may want to consider how long you’re planning to keep this vehicle before spending the money to fix it. In general, most people simply upgrade to a newer model.

In addition, you have to take into account if the car suits your needs. For instance, if you’re expecting kids in the future, then upgrading to an SUV that fits a bigger family is a better choice than spending the money on repairing your sedan’s engine block.


A crack in the engine block is a serious concern requiring costly repair. If all the telltale signs point to a cracked engine block or your service provider gave you this ultimatum, we hope that this article has provided you with the information needed to help you decide what you should do with your car.