Turbocharger: Service and Repair
Fig. 115 Turbocharger Removal (Part 1 Of 2):
Turbocharger And Components:
Removal
Remove the turbocharger assembly with the exhaust fitting, the water pipes A and B, and the oil pipe attached.
Oil Passage Hole:
Caution: After the removal of the oil pipe, take measures to prevent the oil passage hole on the turbocharger assembly from being contaminated with any foreign material.
Turbo Compressor Wheel:
Inspection (Preliminary)
1. Visually check the turbine wheel and the compressor wheel for cracks or other damage.
2. Check to ensure that the turbine wheel and the compressor wheel can be easily turned by hand.
3. Check for oil leakage from the turbocharger assembly.
4. Check for free operation of the wastegate.
5. After removal, check the oil supply and return pipes for blockage or other damage.
6. If any problems are found, replace the components as an assembly.
Disassembly
1. Remove the turbine coupling clamp.
2. Remove the turbine housing.
Compressor Cover Snap Ring:
3. Place the compressor cover assembly on a flat surface (floor) with its end surface down and remove the snap ring with an appropriate pliers.
Cartridge Assembly Removal:
4. Remove the cartridge assembly by tapping the compressor cover with a soft hammer. Normally some resistance will be experienced during removal due to the O-ring on the cartridge assembly.
Inspection
1. Inspect the cast-iron turbine housing for damage, cracks, or evidence of contact between the turbine blades and the turbine housing.
2. Manually position the wastegate valve open and closed to ensure its free operation.
3. Inspect the turbine wheel and the compressor wheel for wear, damage marks, bent or broken blades.
4. Inspect the oil passage in the cartridge assembly for signs of deposits or blockage.
5. Clean the inlet section of the compressor cover with a rag. Inspect the cover for signs of contact with the compressor turbine.
6. If wear marks are present indicating contact, suspect a bad bearing in the cartridge assembly. If there are no indications of improper assembly, replace the cartridge assembly.
Wastegate Actuator
1. Leak test the wastegate valve actuator with a hand vacuum pump. Replace the actuator if it does not hold vacuum.
2. Check the actuator rod to ensure that it is not bent or binding.
Installation Of O-ring:
Assembly
1. Coat the outer circumference of the cartridge assembly O-ring with a thin film of engine oil.
Cartridge Assembly Alignment Pin:
2. Being careful not to damage compressor blades, install the cartridge assembly into the cover. Ensure that the dowel pin is properly aligned and completely seated.
Compressor Cover Snap Ring Installation:
3. Place the cartridge assembly with the compressor housing cover on a flat surface, face down. Install the snap ring, ensuring that the tapered side of the snap ring is up (on the cartridge assembly side).
Turbine Housing Alignment Pin:
4. Install turbine housing onto the cartridge assembly, being careful not to damage the turbine blades. Ensure the dowel pin is properly aligned and fully seated.
5. Install the coupling clamp.
6. Install the wastegate actuator and rod to the compressor housing. connect the rod to the wastegate valve actuating arm.
Wastegate Actuator Operational Test:
1. Connect a suitable pressure tester (with a pressure source) to the pressure hose fitting
2. Apply approx. 11.1 psi (76.7 kPa) pressure to the actuator and check that the rod moves.
Caution: Do not apply a pressure in excess of 12.4 psi (85.3 kPa) to the actuator, damage may result.
3. Ensure that the pressure does not bleed off.
4. If the actuator fails to operate properly, replace the component. Never attempt to adjust the wastegate valve.
Installation
Follow the removal procedures in reverse order paying special attention to the following items.
Torque value:
Air bypass valve:
11 - 16 ft lb (15 - 22 Nm)
Air hose clamps:
3 ft lb (4 Nm)
Air pipe mounting bolts:
9 - 11 ft lb (12 - 15 Nm)
Oil pipe to engine:
10 - 14 ft lb (14 - 19 Nm)
Oil pipe to turbocharger:
20 - 25 ft lb (28 - 34 Nm)
Oil return pipe:
6 - 7 ft lb (8 - 10 Nm)
Wastegate actuator mounting bolts:
7 - 9 ft lb (10 - 13 Nm)
Water pipe "A" mounting bolt:
7 - 9 ft lb (10 - 12 Nm)
Water pipes to turbocharger:
25 - 36 ft lb (35 - 50 Nm)
Water pipe "B" to water inlet pipe:
29 - 36 ft lb (40 - 50 Nm)
Turbo Alignment Surfaces:
Clean the alignment surfaces shown in the image prior to installing the turbocharger.
Turbo Water Pipe Fitting:
Before installing water pipe B, apply machine oil to the inner surface of the pipe flair.