Turbocharger: Service and Repair
REMOVAL
1. Disconnect the battery negative cables.
2. Raise vehicle on hoist.
3. Disconnect the exhaust pipe from the turbocharger elbow (Fig. 23).
4. Lower vehicle.
5. Disconnect the turbocharger air inlet hose (Fig. 24).
6. Disconnect the turbocharger oil supply line and the oil drain tube from the turbocharger (Fig. 25).
7. Disconnect the charge air cooler inlet pipe from the turbocharger (Fig. 25).
8. Remove the turbocharger and gasket from the exhaust manifold.
9. If the turbocharger is not to be installed immediately, cover the opening to prevent material from entering into the manifold.
10. If replacing the turbocharger, transfer the discharge elbow and clamp to the new assembly.
11. Clean and inspect the sealing surface.
CAUTION: The turbocharger is only serviced as an assembly. Do not attempt to repair the turbocharger as turbocharger and/or engine damage can result.
CLEANING
Clean the turbocharger and exhaust manifold mounting surfaces with a suitable scraper.
INSPECTION
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. Note: Some impellers may have a factory placed paint mark which, after normal operation, appears to be a crack. Remove this mark with a suitable solvent to verify that it is not a crack.
3. Visually inspect the turbocharger compressor housing for an impeller rubbing condition (Fig. 26). Replace the turbocharger if the condition exists.
4. Measure the turbocharger axial end play:
a. Install a dial indicator as shown in (Fig. 27).
Zero the indicator at one end of travel.
b. Move the impeller shaft fore and aft and record the measurement. Allowable end play is 0.038 mm (0.0015 inch) MIN. and 0.089 mm (0.0035 inch) MAX. If the recorded measurement falls outside these parameters, replace the turbocharger assembly.
5. Measure the turbocharger bearing radial clearance:
a. Insert a narrow blade or wire style feeler gauge between the compressor wheel and the housing (Fig. 28).
b. Gently push the compressor wheel toward the housing and record the clearance.
c. With the feeler gauge in the same location, gently push the compressor wheel away from the housing and again record the clearance.
d. Subtract the smaller clearance from the larger clearance. This is the radial bearing clearance.
e. Allowable radial bearing clearance is 0.326 mm (0.0128 inch) MIN. and 0.496 mm (0.0195 inch) MAX. If the recorded measurement falls outside these specifications, replace the turbocharger assy
INSTALLATION
1. Install the turbocharger. Apply anti-seize to the studs and then tighten the turbocharger mounting nuts to 32 Nm (24 ft. lbs.) torque.
2. Install the oil drain tube and oil supply line to the turbocharger (Fig. 25). Tighten the drain tube bolts to 24 Nm (18 ft. lbs.) torque.
3. Pre-lube the turbocharger. Pour 50 - 60 cc (2 - 3 oz.) clean engine oil in the oil supply line fitting. Carefully rotate the turbocharger impeller by hand to distribute the oil thoroughly.
4. Install and tighten the oil supply line fitting nut to 20 Nm (133 inch lbs.) torque.
5. Position the charge air cooler inlet pipe to the turbocharger. With the clamp in position, tighten the clamp nut to 11 Nm (95 inch lbs.) torque.
6. Position the air inlet hose to the turbocharger (Fig. 24). Tighten the clamp to 11 Nm (95 inch lbs.) torque.
7. Raise vehicle on hoist.
8. Connect the exhaust pipe to the turbocharger (Fig. 23) and tighten the bolts to 34 Nm (25 ft. lbs.) torque.
9. Lower the vehicle.
10. Connect the battery negative cables.
11. Start the engine to check for leaks.