The turbocharger is designed to increase the overall efficiency of the engine. Power to drive the turbocharger is extracted from the energy in the engine exhaust gas.
The turbocharger consists of a turbine wheel and shaft, a compressor wheel, and a center housing that supports the rotating assembly, bearings, seals, turbine housing, and compressor housing. The center housing has connections for oil inlet and oil outlet fittings.
The turbine housing is a heat-resistant alloy casting that encloses the turbine wheel and provides a flanged engine exhaust gas inlet and an axially located turbocharger exhaust gas outlet. The turbine housing is secured to the turbine end of the center housing.
The turbocharger is mounted on the exhaust outlet flange of the engine exhaust manifold. After the engine is started, the exhaust gases flow from the engine and through the turbine housing causing the turbine wheel and shaft to rotate. See Figure
Schematic Air Flow Diagram
Repair or Replacement of Turbocharger
To determine if repair is possible or replacement of the turbocharger is necessary, perform the following procedure. See Figure
Flowchart for Repair or Replacement of Turbocharger
Removal of Turbocharger
Remove the turbocharger as follows:
Do not attempt to remove carbon or dirt buildup on the compressor or turbine wheels without removing the turbocharger from the engine. If chunks of carbon are left on the blades, an unbalanced condition will exist and subsequent failure of the bearings will result if the turbocharger is operated.
Disconnect the exhaust outlet pipe from the turbine housing of the turbocharger.
Disconnect and remove air inlet hose attached to the compressor housing.
Disconnect and remove CAC ducting at the compressor housing.
Remove two turbocharger bracket nuts from the cylinder block. See Figure
Remove turbocharger bracket to turbocharger housing Allen screws. See Figure
Remove the turbocharger bracket.
Remove four turbocharger mounting nuts from exhaust manifold.
Remove turbocharger from engine.
Inspection of Turbocharger
Similar damage can result from a contaminated exhaust system. Any debris left in the exhaust system after service work can fall back into the exhaust wheel. If large enough, these particles may cause turbine wheel damage at initial engine startup. The exhaust manifold and exhaust piping attached to the turbocharger should also be inspected for debris and cleaned, if necessary, before being installed.
Any time the CAC is removed, all CAC system components must
be inspected to make sure they are clean and free of any casting slag, core sand, welding slag, or any other contaminants that could break free during engine operation and damage the turbine wheel.
Inspect the disassembled turbocharger, discarding any damaged parts, in the following manner:
Visually check for nicked, crossed or stripped oil line threads.