Engine Overhaul: What is it all about?

Engine overhaul
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An engine overhaul is a comprehensive process that involves taking apart the whole engine, inspecting and cleaning its components, and replacing worn or damaged parts. The goal of an overhaul is to restore the engine to optimal performance and extend its service life.

This article will focus on the definition of the engine overhaul since it may be misunderstood, the signs your engine needs, and the overall process.


What Is Engine Overhaul?

Even the most reliable and durable engine will reach the end of its lifespan. In such a case, you are left with only two options: to replace the entire engine or carry out an engine overhaul.

As mentioned, the engine overhaul involves disassembling the engine down to the last screw, repairing and replacing everything necessary, and then reassembling all components to their original condition. It is a very long and complex process during which all engine components are brought to their original working condition, as in the case of a new engine.

However, it is necessary to distinguish whether a fix is a proper or partial engine overhaul. In the case of the latter, only certain parts are disassembled and replaced, and thus it is not ensured that such a fix makes the engine work as the new one.

Signs Your Engine Needs an Overhaul

Recognizing the warning signs that indicate it might be time for an engine overhaul is essential. Some common symptoms include:

  1. Excessive Oil Consumption: If your car is burning through oil at a rapid rate, it could indicate worn piston rings or valve seals.

  2. Loss of Compression: Low compression can result in poor performance, reduced power, and poor fuel efficiency.

  3. Excessive Smoke from Exhaust: Blue or white smoke from the exhaust may indicate oil leaks, worn piston rings, or a damaged head gasket.

  4. Metal Shavings in the Oil: The presence of metal particles in the engine oil can indicate internal engine damage.

  5. Knocking or Tapping Sounds: Unusual noises from the engine can indicate a worn crankshaft, damaged bearings, or other internal issues.

What Does the Engine Overhaul Include?

Engine repair

During the proper engine overhaul, the whole engine is removed from the vehicle and disassembled to the last component. All the valves and crankshaft are ground, the cylinder head and cylinder block are also aligned, and the valves are ground.

On top of that, all seals (for example, head gasket, valve seals, etc.), crankshaft bearings, connecting rod bearings, pistons and their piston rings, water pump, oil pump, and many other components are replaced completely. Finally, all other parts of the engine are thoroughly cleaned to remove grease and dirt.

As you can imagine, all the hours for such a laborious task will quickly add up, and so does the cost. Beware that some repair shops may offer an engine overhaul for a meager price. If it seems too good to be true, they are probably not talking about proper engine overhaul, only about a partial one. While it may be enough for your engine, you'll not get the benefits of the proper engine overhaul.

They will probably grind your cylinder head, replace the head gasket, replace the piston rings, and perform a few other things. However, this is quite far from the proper engine overhaul.

Benefits of an Engine Overhaul

There are several advantages to having your engine overhauled, including:

  1. Improved Performance: An engine overhaul can restore lost power, improve fuel efficiency, and enhance overall performance.

  2. Extended Service Life: By replacing worn parts and addressing potential issues, an engine overhaul can significantly extend the life of your engine.

  3. Reduced Emissions: An overhauled engine will produce fewer harmful emissions, contributing to a cleaner environment.

  4. Increased Resale Value: A well-maintained engine can increase the resale value of your vehicle, making it more attractive to potential buyers.

When Is Engine Overhaul Necessary?

Camshaft gears on a car engine

Engine overhaul is most often carried out in the event that the engine excessively consumes engine oil, rough idling occurs too often, accompanied by a decrease in power, which is caused by a loss of compression in one or more cylinders, or in the event that an engine seizure has occurred.

These problems can occur if any of the components are damaged due to improper handling or if the engine is at the end of its life.

Each engine has its own lifespan specified by the manufacturer. However, the lifespan of the engine is affected by many factors, such as driving style or care and maintenance. It should also be noted that old engines have a longer lifespan compared to modern engines.

The reason is simple: modern engines contain many additional parts susceptible to damage or regular maintenance and care. Simply put, the life of the engine is not infinite, and after a while, it requires some repairs so it may continue to serve.

Watch a short video demonstration of how an engine overhaul can be done: