Turbocharger: Service and Repair

WM 213019 Removing and installing turbocharger on 4.8-litre DFI engines

Technical values

Preliminary work

1. Remove the engine. -> 100119 Removing and installing V8 4.8-litre DFI engine - section on "Removing" 100119 Removing and installing V8 4.8-litre DFI engine
2. Remove primary catalytic converters. -> 267619 Removing and installing primary catalytic converter on V8 4.8-litre DFI engines - section on "Removing" 267619 Removing and installing primary catalytic converter on 4.8-litre V8 DFI engines

Catalytic converter - Turbo engine

3. Drain engine oil.

Removing turbocharger, cylinder bank 1 - 4

Information

- The turbocharger is removed from the engine with all lines fitted. To do this, detach the lines at the connection points on the engine side and remove the turbocharger. Only disconnect the lines on the turbocharger if they are damaged or if the turbocharger has to be replaced.

- When removing the turbocharger take note of the connection points for the lines.

- If the lines that are screwed to the turbocharger need to be disconnected, their position must be marked before disconnecting them. During reinstallation, the lines must be tension-free and must not be bent.

1. Loosen the intake manifold clamp at the turbocharger -2-. Screw on a screw-type clamp. Use a side cutters or a suitable pliers to loosen a clamped one-way clamp (hose clamp). To do this, snip open the one-way clamp. The one-way clamp must not be reused.

Intake manifold on turbocharger

2. Pull off the hose line at the bypass valve control box => Connections. If the line is tight, carefully lever it off with a screwdriver. Then pull off the control pressure line on the turbocharger. To do this, carefully insert a small screwdriver into the metal ring and open it => Diagram shows how to open the circlip.

Connections

Diagram shows how to open the circlip

3. Remove the oil extraction line. To do this, screw off the line at the oil guide housing, turbocharger and on the vent line. Counter with an open-ended wrench. -5- Collect emerging oil.

Oil circuit for turbocharger, cylinders 1 to 4

4. Disconnect the coolant return line next to the generator. To do this, remove the spring band clamp and pull off the rubber line. Then loosen the fastening screw on the holding clamp. => Coolant return line

Coolant return line

5. Detach the turbocharger coolant lines from the coolant hoses or coolant guide and from the holding clamps at the engine (leave attached to the turbocharger) => Turbocharger, cylinders 1 to 4 - cooling.

Turbocharger, cylinders 1 to 4 - cooling

6. Release the sheetmetal holder on the oil supply line. To do this, loosen the fastening nut (M6). -arrow-

Sheetmetal holder on oil supply line

Oil circuit for turbocharger, line connection, cylinders 1 to 4

7. Disconnect the oil supply line at the cylinder head. => Oil supply line

Oil supply line

8. Remove the turbocharger support. To do this, loosen the two fastening screws at the top. Then loosen the lower screw and remove the support. => Turbocharger support

Turbocharger support

9. Remove the turbocharger. To do this, loosen the three fastening screws and remove the turbocharger with the lines attached.

Turbocharger fastening screws

Removing turbocharger, cylinder bank 5 - 8

Information

- The turbocharger is removed from the engine with all lines fitted. To do this, detach the lines at the connection points on the engine side and remove the turbocharger. Only disconnect the lines on the turbocharger if they are damaged or if the turbocharger has to be replaced.

- When removing the turbocharger take note of the connection points for the lines.

- If the lines that are screwed to the turbocharger need to be disconnected, their position must be marked before disconnecting them. During reinstallation, the lines must be tension-free and must not be bent.

1. Remove the right intake manifold on the turbocharger. To do this, loosen the clamp -1-. Screw on a screw-type clamp. Use a side cutters or a suitable pliers to loosen a clamped one-way clamp (hose clamp). To do this, snip open the one-way clamp. The one-way clamp must not be reused.

Intake manifold

2. Loosen and release the turbocharger vent lines at the turbocharger and engine -4-. To do this, loosen the union nut on the oil extraction line (counter.) and the holding clamps.
Remove the oil extraction lines at the oil guide housing and turbocharger -8-.

Oil circuit for turbocharger, cylinders 5 to 8

3. Detach the turbocharger coolant lines from the coolant hoses or coolant guide and from the holding clamps at the engine (leave attached to the turbocharger) => Turbocharger, cylinders 5 to 8 - cooling.

Turbocharger, cylinders 5 to 8 - cooling

4. Pull off the hose line at the bypass valve control box -top arrow-. If the line is tight, carefully lever it off with a screwdriver.

Connections

5. Disconnect the oil supply line at the cylinder head. Then release the sheetmetal bracket. => Oil supply line at cylinder head

Oil supply line at cylinder head

6. Remove the turbocharger support. To do this, loosen the screw on the turbocharger and then loosen the two fastening screws on the cylinder head. Remove the support. => Turbocharger support

Turbocharger support

7. Remove the turbocharger. To do this, loosen the three fastening screws and pull the turbocharger out sideways. The seal between the manifold and turbocharger must not be used again. => Turbocharger fastening screws

Turbocharger fastening screws

Installing turbocharger, cylinder bank 1 - 4

Information

Seals and sealing rings on the lines must always be replaced.

1. Clean sealing faces between the turbocharger and exhaust manifold and replace the seal. -3-

Exhaust manifold on turbo engine M48/51, cylinders 1 to 4

Information

- The turbocharger with lines attached is held in one hand. Use your other hand to fit the lines on the engine first, then secure the turbocharger hand-tight to the exhaust manifold with three screws.

2. Carefully move the turbocharger with lines attached into installation position. Fit new sealing rings hand-tight on the lines.

Information

- The 3 fastening screws of the turbocharger may only be greased on the thread, but not below the head.

3. Screw the turbocharger onto the manifold. Grease the thread of the three fastening screws (M8 x 75) with Microgleit LP 475 mounting paste/000.043.206.95 (status 08/07). Tighten the screws to the specified torque (in two stages). => Turbocharger fastening screws => Initial tightening: 23 Nm (17 ftlb.) ; then => Final tightening: 30 Nm (22 ftlb.)

Turbocharger fastening screws

4. Install the turbocharger support. To do this, tighten the two upper fastening screws (M8 x 20) on the cylinder head to the specified torque. Then insert the lower fastening screw from the front, replace nut and tighten to the specified torque. => Turbocharger support => Turbocharger, cylinders 1 to 4

Turbocharger support

Turbocharger, cylinders 1 to 4

5. Fit the coolant line on the generator. To do this, push on the rubber hose and fit the spring band clamp. Then position the clamp and tighten the fastening screw to the specified torque. => Coolant line => Tightening torque: 10 Nm (7.5 ftlb.)

Coolant line

Turbocharger, cylinders 1 to 4 - cooling

6. Screw in oil supply line with new sealing ring on the cylinder head and tighten to the specified torque. => Tightening torque: 35 Nm (26 ftlb.) Then position the holding clamp and tighten the fastening screw to the specified torque. -arrow- => Tightening torque: 10 Nm (7.5 ftlb.)

Oil supply line

Sheetmetal holder on oil supply line

7. Fit the oil extraction line between the turbocharger and oil guide housing -5-. Replace seals.

Oil circuit for turbocharger, cylinders 1 to 4

Information

- If the hose line of the vacuum unit is difficult to fit, moisten it with water.

8. Attach control line to the turbocharger. Secure the line with a new sheetmetal clip. Then attach the control line to the pressure unit => Control line.

Control line

9. Fit the intake manifold on the turbocharger -1-.

Intake manifold on turbocharger

Installing turbocharger, cylinder bank 5 - 8

Information

Seals and sealing rings on the lines must always be replaced.

Information

- The 3 fastening screws of the turbocharger may only be greased on the thread, but not below the head.

1. Clean sealing faces between the turbocharger and exhaust manifold and replace the seal. -4-

Exhaust manifold on turbo engine M48/51, cylinders 5 to 8

Turbocharger support

Turbocharger, cylinders 5 to 8

5. Screw in oil supply line with new sealing ring on the cylinder head and tighten to the specified torque. => Oil supply line => Tightening torque: 35 Nm (26 ftlb.) Then position the holding clamp and tighten the fastening screw to the specified torque. => Tightening torque: 10 Nm (7.5 ftlb.)

Oil supply line

6. Fit oil extraction line -8-. Fit vent line (counter.) -4-.

Oil circuit for turbocharger, cylinders 5 to 8

7. Fit coolant lines and coolant hoses => Turbocharger, cylinders 5 to 8 - cooling.

Turbocharger, cylinders 5 to 8 - cooling

Information

- If the hose line of the vacuum unit is difficult to fit, moisten it with water.

8. Fit the hose line at the bypass valve control box -top arrow-.

Connections

9. Fit the right intake manifold on the turbocharger. => Intake manifold

Intake manifold

Subsequent work

1. Fit primary catalytic converters. -> 267619 Removing and installing primary catalytic converter on V8 4.8-litre DFI engines - section on "Installing" 267619 Removing and installing primary catalytic converter on 4.8-litre V8 DFI engines
2. Fill in engine oil.
3. Install the engine. -> 100119 Removing and installing V8 4.8-litre DFI engine - section on "Installing" 100119 Removing and installing V8 4.8-litre DFI engine