Turbocharger Cleaning and Inspection

Completely inspect the turbocharger and all other engine components that may cause similar conditions before replacing the turbocharger.

Use the following information to diagnose problems caused by the turbocharger.

The turbocharger is serviced as a complete unit.

IMPORTANT: Oil residue on the turbocharger compressor wheel is normal with a closed PCV system.
1. Remove the turbocharger oil return pipe bolts.
2. Remove the turbocharger oil return pipe and gasket.
   Fig 1: View Of Oil Return Pipe Bolts

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3. Clean mating surfaces.
4. Inspect for damage to the compressor wheel, compared to a normal compressor wheel.
   Fig 2: Identifying Normal Compressor Wheel

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5. Inspect for damage to the compressor wheel, by a soft object.
   Fig 3: Identifying Damaged Compressor Wheel (Soft Object)

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6. Inspect for damage to the compressor wheel, by a hard object.
   Fig 4: Identifying Damaged Compressor Wheel (Hard Object)

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7. Inspect compressor blades for heavy rubbing.
   Fig 5: Identifying Compressor Blades (Heavy Rubbing)

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   Ensure that the following conditions do not exist on the compressor wheel blades:

   • Cracks
   • Bends
   • Erosion of the blades
   • Broken blades
8. Check the housing for signs of rubbing.
9. Install the turbocharger oil return pipe and new gasket.
   Fig 6: View Of Oil Return Pipe Bolts

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10. Install the turbocharger oil return pipe bolts.

    Tighten:  Tighten the turbocharger oil return pipe bolts to 21 N.m (15 lb ft).

IMPORTANT: If the cooling outlet hose eye bolts were removed, install the longer bolt (1) with two holes, in the top location. Install the shorter bolt (2) in the lower location.
Fig 7: Identifying Cooling Outlet Hose Eye Bolts
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11. Inspect the coolant outlet lines for damage.
12. Clean the turbocharger inlet duct.
13. Clean the turbocharger inlet duct mating surfaces.
14. Inspect the turbocharger inlet duct for cracks.
    Fig 8: Identifying Turbocharger Inlet Duct Inspection Areas

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15. Inspect the turbocharger inlet duct mating surfaces for damage.
16. Replace the turbocharger inlet duct if any damage is found.

    Tighten:  Tighten the inlet duct clamp to 5 N.m (44 lb in).