BMW vehicles are already known for their unique design, performance and engineering. However, well-functioning components also stop working sometimes. In the cases where the engine stops working, people often question whether they should go for a new engine or rebuilt engine. It is pretty clear that the new engine works better but comes with a heavy cost, which makes the rebuilt engine a better choice to consider. In this article, you will learn about all the benefits of rebuilding a BMW engine to help you decide to either replace or rebuild your engine.

Why do Engines Fail?

Many engines, even of good quality, reach catastrophic failure when the service and maintenance have been ignored for a long time. The internal components experience systems failure or oil starvation, which results in the failure of the entire engine. Failed engines are replaced with reconditioned, rebuilt or new engines. BMW 123D engine rebuilds are expensive but not more than the new engine. The common reasons for engine failure come from oil starvation, damaged oil pump and broken water pump/thermostat. When the failure of major components occurs, it will result in a non-working vehicle that will require a new or rebuilt engine.

When it comes to the available options for engine replacement, a new engine comes with a heavy cost, which everyone cannot afford. According to the needs and budgets of different people, the failed engine is replaced with a suitable engine.

What Happens When an Engine is Rebuilt?

Bmw Engine M3 - Free photo on Pixabay

Rebuilding an engine involves the removal of the engine from the vehicle and dissembling it. Once after dissembling, cleaning and inspecting, all the damaged parts are replaced with new or remanufactured parts. The complete dissembling of the engine is commonly referred to as ‘carb to pan’, an old description used when engines had carburettors. Usually, new gaskets seals and used during assembling of the rebuilt engine to meet the standards of BMW. Timing belts, bearings, oil pumps, O rings and valves are the most common components to be replaced. However, the major components replaced during engine rebuilding are camshafts, pistons and crankshafts. While installing the newly rebuilt engine, the ECU is programmed to communicate with the engine.

If severe damage has been found in your engine, the engine block is bored to align the crankshaft. New pistons are installed by boring the cylinders. Rebuilding an engine is full of extensive work and also needs to be done by a professional. The wrong assembly of the components can lead to further damage. However, replacing your engine with a rebuilt engine assures you the longevity and efficiency of the engine. So, if your engine block has been completely damaged due to a broken crankshaft or connecting rod, you can consider the replacement with the new engine. However, in the case of the cracked exterior of the engine block, having the engine rebuilt is a more realistic option available.

What are the Benefits of Rebuilding an Engine?

The main benefit you get with the rebuilt engine is that it gives you peace of mind that every component of your engine has been closely inspected. Secondly, during the rebuilding of the engine, all the worn and damaged parts are replaced with new parts, which also ensures the longevity of your engine. Another benefit of rebuilding an engine is that you are recycling the old engine parts and playing part in reducing the amount of waste in the environment. In many cases, the rebuilt component works better than the new component, which ensures you quality with affordability. Asides from all these benefits, the most interesting benefit of rebuilding an engine is the programming of ECU to communicate with the originally installed engine.

In most cases, when the new engine is installed in the vehicle, the ECU experiences problems in connecting and communicating with the new engine. In such cases, the engine will require either replacement or reprogramming of the ECU. If you have a situation where you need to decide between a new engine and rebuilt engine, it is always advised to go for the repairing of your existing engine. During the rebuild, the components of the damaged engine are replaced with the new OEM replacement parts to reduce the risks of issues.


Your vehicle’s engine is comprised of the number of parts that are constantly moving and are subjected to high pressure and temperature on daily basis. After covering its maximum mileage, it starts showing signs of wear and tear even when maintained properly. Here you are often left with few choices, such as trading the vehicle, buying a new engine or rebuilding the old engine. Rebuilding is a better option if you are looking for affordability as well as functioning. You can easily get your vehicle installed with the engine rebuilt according to prescribed standards and specifications. So, don’t wait and talk to your mechanic about rebuilding your engine.