Turbochargers can operate at speeds of over 200 000 RPM, driven by exhaust gasses of over 950 °C. At these speeds the centrifugal forces acting on the compressor and turbine wheels are a major factor in determining the normal operating limits of operation. Over speeding occurs when the rotating assembly spins at a greater speed than its operational limits which results in damaged to the turbine wheels.
Causes of turbocharger over speeding
A blocked/partially blocked air filter or piping causing reduced compressor loads and efficiency.
Sticking vanes caused by excessive carbon deposits.
Damaged/cracked air pipes and air leaks that reduce turbocharger efficiency.
Faulty or worn injectors resulting in over fuelling.
Non standard (tampering) adjustments of waste gate and VNT actuators.
Faulty ECU control components/system.
Incorrect turbocharger selection.
Preventing turbocharger over speeding
Check for a blocked air filter or restrictions in air piping.
Check for damaged/cracked air pipes and air leaks.
Turbochargers are factory set to suit specific uses. Alterations to these settings can lead to turbocharger failure and will void warranties.
Always fit the correct turbocharger as per vehicle/engine manufacturers specifications.
Check for correct operation of the ECU and fuel system components..
Check for smooth operation of the actuator.