This kit has all the wear items needed to reman a turbocharger IF there is no damage to the internal components (only wear). If the turbo has failed in the field and internal components have contacted each other or if some foreign matter has entered the turbo causing damage, then further parts past the service kit are needed to repair the unit. It is advised that a turbo specialist repair the unit as the job would need special knowledge to repair.Kit contents include:- Journal Bearings
- Piston Rings
- O-rings
- Snap Rings
- Thrust Bearing
- Thrust collars
- Shaft Nuts
- Mounting bolts
- Gaskets if required
- Clamp plates if required
- Heat Shield if required
Common Causes for Turbocharger Failure
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3. Common Causes for Turbocharger Failure
This section will discuss the four primary causes for turbocharger failure. It is important to note that when a
turbocharger fails for any reason, there is almost always secondary (and often more severe) damage
caused by the resulting shaft motion. You must look passed the obvious damage to locate the root cause.
Note that some “cause of failure” descriptions contain very similar indicators so be sure to read through all
prior concluding your analysis.
3.1. Lack of Lubrication / Contaminated Oil (Causes over 40% of Failures)
The lubrication system plays a vital role in extending the life expectancy of a turbocharger by lubricating,
cooling, and cleaning the bearings. The shaft and bearings must “float” on a constant, clean film of oil to
prevent direct contact with each other which will result in damage. Any lack of oil flow or foreign
contaminant (i.e. dirt, sand, or metal shavings) in the oil will cause excess wear and/or scaring on the
bearing surfaces. This wear will often increase the clearances between rotating components resulting in
excess “shaft motion”. A large amount of “shaft motion” is detrimental to the life of a turbocharger.
Common causes of lubrication failure:
• Low engine oil pressure/level
• Obstructed oil supply / drain lines
• Improper weight of oil
• Contaminated oil
• Fast starts in cold weather
• Hot shutdown (Figure 6) - Engine is shutoff at high
rpm/temp; instant oil flow loss causing overheating
• Engine Blow-by
A. External Lack of Lubrication:
• Occurs when anything exterior to the turbocharger is affecting the oil flow (supply or drain lines,
engine blow-by, etc.).
• All thrust & journal bearings as well as the turbine shaft will show signs heat discoloration (Figure
7) as well as wear from the resulting shaft motion. The wear will appear smooth or “wiped”
(Figures 8 & 9) and should not have any significant scaring (Figures 10 & 11).
• Unwarrantable: The cause of this failure is external to the turbocharger.
B. Internal Lack of Lubrication:
• Visible when one or more, but not all, of the bearings show the above mentioned wear. This
indicates that only one of the oil feed lines have been blocked from either contaminated oil (see
below) or a manufacturers defect.
• Warrantable: If there are no signs of contaminated oil.
• Unwarrantable: If there are signs of contaminated oil or “coking” of the oil caused by overheating.
C. Contaminated Oil:
• Occurs when abrasive material such as dirt, sand, or metal shavings enters the oil passages. This
is generally easy to notice as the bearings and connecting components will show abnormal
grooves and scratches (Figures 10 & 11). This may also cause a lack of lubrication failure as
noted above.
• Unwarrantable: The cause of this failure is related to the installation or oil quality within the vehicle.