LEMON Manuals: Even more car manuals for everyone
Home >> Nissan-Datsun >> 2021 >> NV2500 HD S >> Repair and Diagnosis >> External Pages >> Different car >> Section 126 (Engine Mechanical (CUMMINS 5.0L) (1 Of 2)) >> Basic Inspection >> Turbocharger >> Inspection >> Malfunctioning Turbocharger

Malfunctioning Turbocharger

WARNING: This page is about a different car, the 2018 Nissan Titan XD. However, it is still accessible from the selected car via links, so may be relevant.
  1. A malfunction of the internal components of the turbocharger can reduce its effectiveness. A bearing malfunction can produce friction, which will slow the speed of the rotor assembly. Worn bearings can also allow the blades of the rotor assembly to rub the housing, reducing the rotor assembly speed.
    NOTE: Lower pitched sounds or rattles, at slower engine speeds, can indicate that debris is in the system or that the rotor assembly is touching the housings. If there is a complaint for noise, low power, engine response, or oil consumption, verify the conditions under which the complaint occurred.
  2. O-rings (A) are used on each end of the rotor assembly. The primary function of the O-rings (A) is to prevent exhaust gases and compressed air from entering the turbocharger housing. Oil leaks from the O-rings are rare, but it can occur.
    GNSALBIA2299Z-299Courtesy of NISSAN NORTH AMERICA, INC.
  3. Because this engine is equipped with a closed crankcase ventilation system, a light coating of oil in the turbocharger compressors is normal. If oil is pooled further investigation is required.
    NOTE:
    • Excessive crankcase pressure will not allow the oil to drain from the turbocharger. This will load the bearing housing and allow oil to leak past the O-rings and into the intake system and exhaust system of the engine.
    • If O-ring leaks into the exhaust occur, the aftertreatment system must be inspected for reuse.
  4. A restricted or damaged oil return connection will cause the turbocharger housing to be pressurized, causing oil to migrate past the O-rings on both the intake and exhaust side of the turbocharger.
  5. Additionally, high intake or exhaust restrictions can cause a vacuum between the compressor and the turbocharger housing, resulting in oil leaking past the O-rings at the intake side.
    NOTE: If this occurs, it is necessary to flush the charge-air cooler to clean the oil from the intake system, clean the intake manifold, and clean the charge-air cooler.
  6. Make sure the rotary turbine control valve is functioning properly.
  7. The rotary turbine control valve can be tested using the RTCV Hysteresis Test, which can be started through CONSULT. The test confirms the rotary control valve can achieve all positions in its operating range. The test results determine if further inspection is required of the following components:
    • Rotary turbine control valve linkage
    • Rotary turbine control valve actuator
    • Turbocharger. Refer to Exploded View .
scientia non olet · About LEMON Manuals