An internal combustion engine is subject to progressive wear during operation. Even with good and regular maintenance, engine damage cannot always be avoided at high mileage. In this case, an engine overhaul can be the right solution. Here you can find out everything about this type of repair and get an overview of the costs of engine overhaul. You will also find out what alternatives there are to engine reconditioning.

Definition and goal of engine overhaul

An engine overhaul aims to fully restore the function of the engine after it has been damaged. For this purpose, the engine is usually disassembled and defective parts are replaced or repaired. Not every workshop offers the service of an engine overhaul. Often, services such as engine overhaul are outsourced to an external company. The scope of an engine overhaul is not fixed and can include various services and components. Before placing an order for engine overhaul, it is advisable to consult the workshop. A corresponding offer should include a list of the scope of the engine overhaul and an estimate of the costs involved.

This is how engine overhaul works

A comprehensive engine overhaul involves numerous work steps that must be coordinated. Engine overhaul also requires extensive expertise. Specialized companies often have years of experience in the field of engine overhaul. They can reliably identify the reason for engine damage, limit the costs of engine overhaul and identify solutions. Not all steps are always necessary to repair the engine.

Diagnosis of the damage to the engine

In the first step of the engine repair process, an expert engine technician narrows down the damage at hand. Based on his experience, the technician can assess which parts on the engine are defective and which components need to be replaced. Diagnosis is aided not only by know-how often acquired over years, but also by the latest equipment for analyzing engine damage.

Removing defective engines from the car

In order to carry out engine repair, the engine usually has to be removed from the car. The engines themselves must also be disassembled in order to perform a general overhaul or repair. The removal from the vehicle can be done by almost any workshop. Sometimes this service is also performed by the repairer who carries out the overhaul.

Disassembly of engine and components

Before the actual overhaul, the engine is disassembled into its individual parts. In addition, the engine parts are often cleaned in order to better inspect them for hidden damage. The extent of disassembly depends on the type of engine damage. Defective components and wear parts are sorted out in this step.

Processing the engine block after engine damage

In the course of engine overhaul, it is often necessary to rework the engine block. Especially in the area of the cylinders, engines with high mileage show wear here. This step is also often necessary after engine damage due to piston seizure or torn valves. Sealing surfaces are machined or the cylinders are bored and honed.

Repairing damaged cylinder heads

The cylinder head is one of the most important engine components in an internal combustion engine. During an engine overhaul, this component is therefore extensively inspected and reworked. Cracks in cylinder heads can be detected using special measuring technology. Depending on the damage, repair or replacement is possible. Valves and valve guides can be easily replaced during the overhaul.

Crankshaft inspection and repair

In engines, the crankshaft is a central point where many forces interact. In the course of a comprehensive engine overhaul, the component is therefore checked and repaired or optimized if necessary. The crankshaft can also be replaced during the overhaul. Crankshafts can also be finely balanced so that the engine runs particularly smoothly after overhaul.

Overhauling connecting rods and camshafts

Engine parts such as connecting rods and camshafts can be inspected and repaired during a comprehensive overhaul. After removal from the engine, the connecting rods can be honed if necessary and the connecting rod bushings renewed. The camshaft for controlling the valves can also be optimized and, if damaged, reworked or replaced.

Checking and repairing the ancillary units

Not only the engine itself, but also the ancillary units should be checked during an engine overhaul. This step is carried out as standard during general overhauls of engines. Add-on parts such as oil pumps, fuel injection parts or the turbocharger are repaired or replaced if necessary.

Assembling and checking the engine

After all major engine components have been checked, cleaned or repaired, the technicians reassemble the engine. During this process, all engine components are carefully assembled according to manufacturer specifications. A test of the freshly overhauled engine then takes place. The engine must prove its performance on a dynamometer.

Installation of the engine in the car

As a final step, reconditioned engines are reinstalled in the vehicle. This work is usually done by the workshop that removed the defective engine. Further maintenance is also carried out here. After the engine has been installed, the mechanics fit missing add-on parts and top up fluids. This is followed by comprehensive tests of the engine as well as test drives.

The advantages of engine reconditioning

Engine reconditioning offers many advantages. For example, large parts of the engine can be preserved when the engine is reconditioned. Compared to replacing engines, this often results in lower costs for engine overhaul. In addition, engine overhaul reduces the burden on the environment and saves valuable resources. Engine overhaul allows many engine parts to be reused. Defective components and wear parts can be repaired or recycled. For cars such as classics or high-quality sports cars, engine reconditioning offers another advantage. Here, the engine installed at the factory ensures the originality of the vehicle. If the engine number and chassis number match, the vehicles often increase in value.

The costs of an engine overhaul

The cost of an engine overhaul depends on numerous factors. These include the type of engine damage and the extent of engine overhaul needed. Depending on which parts need to be replaced, the price of the engine repair varies significantly. The price of repairing individual engine parts such as the camshaft or cylinder head usually ranges between 150 and 500 euros. For a complete engine overhaul, costs are usually higher, starting at 3500 euros. In addition to the scope of the engine overhaul, the manufacturer of the engine is also decisive for the subsequent price. The prices for spare parts vary depending on the brand. The cost of the overhaul also varies depending on the engine variant. In addition to the price of the engine overhaul, there are also costs for the assembly and disassembly of the engine. Depending on the vehicle model, the cost of removing the engine and installing it later varies. Workshop costs thus vary depending on the vehicle.

Price comparison: engine overhaul vs. new engine

Engine overhaul does not make sense in all cases. If all engine components are already heavily worn, replacing the engine is often a good alternative. The same applies whenever the damage to the engine is particularly severe. With costs starting at 5000 euros and more, completely new engines are often priced higher than engine overhauls. A factory-new engine is not always available for all passenger cars. Especially for an older vehicle, finding a new replacement engine can be difficult. Also, not all brands offer new engines for all models. After consulting with the repair shop, it is often possible to install an engine that has been reconditioned by the manufacturer. In addition, many reconditioners offer overhauled engines in exchange.