There are many causes for a turbocharger to fail. They include Heat buildup, Negative pressure differential, and Oil starvation. Depending on the cause, the turbocharger may be damaged internally. This can consist of a valve or piston fragment that passes through the turbine wheel and lodges somewhere in the exhaust system. If this is the case, the driver may have noticed poor performance before the turbo failed.
Negative pressure differential
A negative pressure differential causes a turbocharger to break down, which can be caused by a few problems. The first is the presence of a broken thrust bearing, which is usually paired with a fractured thrust ring. Another problem is when the turbo needs to be appropriately matched to the engine. Though a turbocharger can withstand average pressure differentials and surges, the more frequent issues it encounters, the more likely it is to fail. The thrust bearing is an essential component of the turbocharger, limiting end play and preventing excessive wear on the turbine shaft.
Another common cause is a damaged air filter. In extreme cases, a broken air filter can result in a failed turbo. In other cases, a foreign object can enter the turbocharger. It is essential to check all intake and exhaust port connections to ensure no leaks. If there are leaks in any of these areas, you must immediately replace them. In other cases, a broken turbo may result from catastrophic engine failure. If this is the case, you can flush the entire oil pan and replace the lines. Alternatively, you can lubricate the turbocharger with a large syringe placed in the oil supply line.
There are many reasons for turbocharger failure. It can begin in one area and spread to different turbocharger parts. Once you pinpoint the cause of the loss, you can correct the problems and prevent future failures. Performing a failure analysis is similar to performing a medical diagnosis. Using a list of symptoms, you look for a specific bug and apply the proper remedy. If you’re unsure, you can consult a professional.
Oil starvation
Oil starvation can be a significant cause of turbocharger failure. The problem can develop for various reasons, including a bent oil feed pipe, low oil in the sump, and a blocked oil inlet gasket. Regardless of the cause, preventing oil starvation is essential to keeping your turbocharger working as it should.
Oil starvation is the most common cause of turbocharger failure. It can cause the turbo to fail prematurely, leading to catastrophic damage to the engine. It can also be caused by a poorly installed or clogged oil filter. Foreign objects can also block the piping and hoses connecting the turbocharger to the machine. The turbocharger could fail due to restricted airflow if these issues are not addressed. The piping and hoses should be reinstalled carefully.
Oil starvation can also occur due to excessive carbon buildup. This carbon builds up, clogs the oil supply pipes, and reduces oil flow to the turbo. This can also lead to the failure of the bearings. Metal shavings can also enter the oil system and wear out the turbo.
Oil starvation is a severe problem because it places extreme pressure on the turbocharger’s bearings. Because they spin at over two40,000 rpm, the additional stress increases the chances of bearing wear. This can lead to catastrophic failure, as the turbo is rendered useless.
Even a slight reduction in oil pressure can kill a turbo within seconds. The result is blueing on the turbo shaft and seized bearings. There are several causes of oil starvation, but a broken oil feed pipe is the most common.
Heat buildup
When you see your turbo failing, you should start by inspecting it to make sure there’s no foreign body in the turbo’s internal parts. Foreign bodies can damage the turbo’s turbine blades, bearings, and seals. They can also cause the rotary assembly to become unbalanced, affecting the shaft’s movement within the housing. You should also pay special attention to the EGR conduits, which should be free of foreign material.
Oil starvation is another common problem that damages turbochargers. It can be caused by debris and foreign particles lodged inside the engine oil. These contaminants interfere with the proper functioning of the oil and cause damage to other parts of the turbocharger. The affected components will show poor functioning, including heavy scoring on the main shaft and bearing surfaces.
A lack of lubrication can destroy a turbo in seconds. When the oil supply is disrupted, the bearings begin to spin at high speeds, creating extreme heat. The shaft will start to turn bluish, and the axial direction may also show damage.
There are several common causes of turbocharger failure, and it is essential to recognize which part failed. It’s helpful to note what caused the loss, so you can take steps to avoid it in the future. It’s possible to repair a turbocharger by following these steps.
Almost 90% of turbocharger failures are caused by issues with the oil used to lubricate the turbo. This can be caused by oil contamination, blocked pipes, or lack of priming on the fitting.
Shaft seizure
Shaft seizure can lead to catastrophic failure of the turbocharger. This condition occurs when there is a lack of oil in the turbocharger, and it can cause the shaft to seize and fail. The post is attached to the turbine and rotates at very high speeds, which can result in the pole touching the bearing surface and causing it to seize. In extreme cases, it can even cause the turbocharger to fail altogether.
The first symptom of this condition is that the compressor wheel is not spinning. This is a sign of shaft seizure and needs to be examined. There are several possible causes of this condition. These include oil starvation, broken or blocked pipes, and lack of priming of the fitting.
Another cause of shaft seizure is excessive wear of the bearings. This is due to the granular carbon deposits on the bearing surfaces—these deposits damage bearing surfaces and restrict the space for oil films to form. In addition, they also plug up bushing lubrication holes. These deposits can also damage the turbocharger’s bearing system. If these conditions are not corrected, the shaft can break or seize, failing.
The problem usually begins in a cluster of failures in the sixth year of ownership. In a typical case, this problem manifests as a sudden loss of power or strange hissing. The vehicle’s engine service light may also temporarily or permanently illuminate.
The NTSB recommended that the FAA include information about the causes of turbocharger failure in its airworthiness directive. The FAA agreed and required the manufacturers to have the information in new AFMs.
Cycle fatigue
Cycle fatigue is a type of failure that occurs in a turbocharger over many cycles. This type of failure is typically caused by minor elastic strains that occur over a long period. The stresses come from mechanical and thermal stresses at various frequencies. Some examples of this stress are residual stress, assembly load, and strongly non-uniform temperature distribution.
A turbocharger is commonly overloaded in a competitive environment, so it’s not uncommon for turbos to fail due to fatigue. In these cases, the turbocharger’s compressor wheel may wear down to the point that it bursts or dies. The blades are often severed when this occurs, causing severe damage to the engine.
A failing turbo will make a whining noise when engaged. This sound may accompany other symptoms, including a loss of power or engine performance. A turbo will sometimes still function correctly, despite its failure. This can be caused by a blockage of the PDF, which can cause a buildup of contaminants that will cause the turbo to fail.
The exact cause of a turbocharger failure can be challenging to determine. Luckily, there are several ways to diagnose a problem. Identifying the problem will help you isolate the problem and take corrective action to prevent a repeat occurrence. The first step to engine health is understanding how the turbocharger works. By understanding how your turbocharger works, you’ll be able to identify if the problem is due to a component or a combination of ingredients.
Cycle fatigue is a failure that occurs when stress exceeds the material’s yield strength. A turbocharger that has experienced this type of fatigue failure is considered high-cycle fatigue. Its failure time depends on the number of cycles, as the number of cycles is proportional to the amount of stress applied.
