Turbocharger: Service and Repair

TURBOCHARGER

REMOVAL
GAS ENGINES

CAUTION: If turbocharger is replaced due to a bearing failure, replacement of the oil pressure feed line is required. Oil return tube should be cleaned also.

NOTE: The turbocharger and exhaust manifold are serviced as an assembly. Do Not attempt to remove the turbocharger from the exhaust manifold. Exhaust leaks will result. It is recommended that the turbocharger elbow be replaced along with the turbochargerexhaust manifold assembly.





1. Disconnect negative battery cable.
2. Drain cooling system.
3. Remove air cleaner housing and lid.
4. Disconnect clean air hose (1) from turbocharger (2).





5. Disconnect throttle and speed control cables at throttle body.
6. Disconnect electrical connectors from the following components:
^ Inlet Air Temperature (IAT) Sensor
^ MAP Sensor
^ IAC Motor
^ Throttle Position Sensor
^ Ignition Coil Capacitor
^ Upstream Oxygen Sensor
7. Disconnect air inlet hose at throttle body (1).





8. Disconnect vacuum hoses at throttle body and upper intake manifold.
9. Remove upper intake manifold support bracket (2).





10. Remove upper intake manifold.

CAUTION: Cover lower intake manifold opening with suitable cover to prevent any foreign objects from entering.

11. Disconnect oil supply line (1) at turbocharger.
12. Remove coolant return line (2).





13. Disconnect vacuum hoses from turbocharger.
14. Raise vehicle on hoist.
15. Disconnect muffler ground strap. Remove muffler.
16. Disconnect downstream oxygen sensor.
17. Remove fasteners (3, 4) securing catalytic converter (5) to exhaust manifold.
18. Remove catalytic converter and intermediate pipe as an assembly.





19. Remove turbocharger to charge air cooler hose assembly (2).





20. Remove turbocharger lower heat shield (1).
21. Remove turbocharger elbow support bracket (4).
22. Remove turbocharger support bracket (2).
23. Remove turbocharger elbow (3).
24. Remove lower exhaust manifold fasteners that are accessible while vehicle is on hoist.
25. Lower vehicle.
26. Remove upper exhaust manifold fasteners.
27. Remove turbochargerexhaust manifold assembly from above/between the engine and cowl panel.
28. Remove and discard exhaust manifold gasket.

INSPECTION - TYPICAL TURBOCHARGER
Visually inspect the turbocharger and exhaust manifold gasket surfaces. Replace stripped or eroded mounting studs.





1. Visually inspect the turbocharger for cracks. The following cracks are NOT acceptable:
^ Cracks in the turbine and compressor housing that go completely through.
^ Cracks in the mounting flange that are longer than 15 mm (0.6 inch).
^ Cracks in the mounting flange that intersect bolt through-holes.
^ Two (2) Cracks in the mounting flange that are closer than 6.4 mm (0.25 inch) together.
2. Visually inspect the impeller and compressor wheel fins for nicks, cracks, or chips.
3. Visually inspect the turbocharger compressor housing for an impeller rubbing condition. Replace the turbocharger if the condition exists.

INSTALLATION

CAUTION: If turbocharger is replaced due to a bearing failure, replacement of the oil pressure feed line is required. Oil return tube should be cleaned also.

NOTE: The turbocharger and exhaust manifold are serviced as an assembly. Do Not attempt to remove the turbocharger from the exhaust manifold. Exhaust leaks will result. It is recommended that the turbocharger elbow be replaced along with the turbochargerexhaust manifold assembly.





1. Clean gasket sealing surfaces. Replace exhaust manifold gasket. DO NOT APPLY SEALER TO GASKET.

NOTE: Stainless steel layer of exhaust manifold gasket goes against cylinder head, graphite layer of gasket goes against manifold surface.

2. Turbochargerexhaust manifold assembly is installed from above/between the engine and cowl panel.
3. Position turbochargerexhaust manifold assembly in place. Gradually tighten fasteners, starting at center and progressing outward in both directions to 28 Nm (250 inch lbs.). Raise and lower vehicle for fastener access as necessary. Repeat tightening procedure until all fasteners are at specified torque.
4. Install turbocharger elbow. Torque fasteners to 28 Nm (250 inch lbs.).
5. Install turbocharger upper heat shield. Torque fasteners to 28 Nm (250 inch lbs.).
6. Install turbocharger coolant supply line. Install NEW washers. Torque banjo fitting bolt to 37 Nm (27 ft. lbs.). Torque flared fitting to 31 Nm (23 ft. lbs.).
7. Replace oil return tube gasket. Install oil return tube. Torque fasteners to 12 Nm (105 inch lbs.). Make sure heat shield for oil return line is properly installed.
8. Install turbocharger support bracket. Torque M8 fasteners to 28 Nm (250 inch lbs.) and M10 fasteners to 54 Nm (40 ft. lbs.).
9. Install turbocharger elbow support bracket.
10. Install turbocharger to charge air cooler hose assembly.
11. Install catalytic converter and intermediate pipe as an assembly.
12. Install fasteners securing catalytic converter to exhaust manifold. Torque fasteners to 28 Nm (250 inch lbs.).





13. Install muffler. Connect muffler ground strap.
14. Connect downstream oxygen sensor.
15. Lower vehicle.
16. Connect vacuum hoses to turbocharger.
17. Install coolant return line. Install NEW washers (2). Torque banjo fitting bolt to 37 Nm (27 ft. lbs.).
18. Connect oil supply line at turbocharger. Torque flared fitting to 31 Nm (23 ft. lbs.).

NOTE: The lower heat shield tabs must over lap the upper heat shield to prevent fatiguing and premature
failure of the union.

19. Install turbocharger lower heat shield. Torque fasteners to 28 Nm (250 inch lbs.).
20. Install upper intake manifold.
21. Install upper intake manifold support bracket.
22. Connect vacuum hoses at throttle body and upper intake manifold.
23. Connect air inlet hose at throttle body
24. Connect electrical connectors to the following components:
^ Inlet Air Temperature (IAT) Sensor
^ MAP Sensor
^ IAC Motor
^ Throttle Position Sensor
^ Ignition Coil Capacitor
^ Upstream Oxygen Sensor
25. Connect throttle and speed control cables at throttle body.
26. Connect clean air hose to turbocharger.
27. Install air cleaner housing and lid.
28. Fill cooling system.
29. Change oil and filter.
30. Connect negative battery cable.
31. Start the engine and inspect for exhaust leaks. Repair exhaust leaks as necessary
32. Check the exhaust system for contact with the body panels. Make the necessary adjustments, if needed.