Removal and installation of the power unit (Mercedes-Benz G-Class W463)

Note: The engine is removed together with the transmission.

Disconnecting the electrical wiring

Petrol models

1. On models with the corresponding configuration (code ET2), activate the service mode of the TELE AID emergency call system (see Section Activation/deactivation of the service mode of the TELE AID emergency call system).

2. Turn on the auxiliary battery and connect it to the standard battery, then disconnect the negative wire from the latter, insulate the pole terminal. If the battery is removed from the car, also disconnect the positive wire from it.





3. Remove the air tract resonator chamber with the water collector (see Chapter Fuel and exhaust systems).

4. Remove the engine wiring panel cover (1) located in the passenger compartment.

5. Disconnect the electrical wiring connectors (A) on the ME-SFI control module (N3/10), - press the latch down and turn the locking lever.

6. Remove the glove box (see Chapter Body).

7. Disconnect the contact connector at the module block/engine separation unit (X35/26).

8. Disconnect the electrical wiring (4) of the front signal sensing and activation module (SAM) (N10/1).

9. Pull the interior engine wiring harness through the pass-through hole in the body panel, being careful not to damage the insulation.

10. Disconnect the lambda probe wiring connectors (G3/3), G3/4, G3/5 and G3/6) (see illustration Powertrain installation details on petrol models).

11. Remove the left ignition coil (see Chapter Engine electrical systems).

12. Open the cover (2) of the auxiliary power supply connection unit for emergency starting.

13. Unbolt the wire (3) from terminal 30 of the terminal block (X4/30) of the engine circuit 30.

14. Disconnect the ground bus W11/5 from the starter.

15. Disconnect the electrical wiring connector (X22/2) on the transmission.

16. Unbolt the transmission ground bus (W49) from the frame.

17. Loosen the bolt (13) and remove the transmission output speed sensor (B49) (speed sensor), - prepare a replacement sealing ring.

18. Installation is carried out in the reverse order - if the corresponding configuration (code ET2) is installed, deactivate the service mode of the TELE AID system (see Section Activation/deactivation of the service mode of the TELE AID emergency call system).



19. Finally, read the DTC codes and clear the on-board diagnostic system memory using the STAR DIAGNOSIS scanner (6511 1801 00) (See Chapter Engine electrical systems).

Diesel models

M612

1. On models with the corresponding configuration (code ET2), activate the service mode of the TELE AID emergency call system (see Section Activation/deactivation of the service mode of the TELE AID emergency call system).

2. Disconnect the ground wire from the battery (see Chapter Engine electrical systems).

3. Open the cover (1) of the auxiliary power supply connection unit for emergency starting.

4. Unbolt the wire (2) from terminal 30 of the terminal block (X4/30) of the engine circuit 30.

5. Remove the air tract resonator chamber with the water collector (3) (see Chapter Fuel and exhaust systems).

6. Remove the cover (4) on the rear bulkhead of the engine compartment.

7. Unlock and disconnect the contact connectors (5 and 6) on the CDI control module (N3/9), - access to connector (5) is available after disconnecting connector (6).

8. Remove the cover on the left under the instrument panel and disconnect the connectors (7 and 8) in the front fuse/relay box (N10/1).



9. Release the engine wiring harness (9) through the passage in the body panel, being careful not to damage the insulation.

10. Release the retainer (10) and remove the bandages (11) on the splash guard and the cooling tract line.

11. Disconnect the connectors (12) at the preheating system output (N14/2).

12. Disconnect the electrical wiring connector (X22/2) on the transmission.

13. Unbolt the transmission ground bus (W49) from the frame.

14. Installation is carried out in the reverse order - if the corresponding configuration (code ET2) is installed, deactivate the service mode of the TELE AID system, see Section Activation/deactivation of the service mode of the TELE AID emergency call system).

15. Finally, read the DTC codes and clear the on-board diagnostic system memory using the STAR DIAGNOSIS scanner (6511 1801 00) (See Chapter Engine electrical systems).

M628

1. Disconnect the ground wire (W10) from the battery (see Chapter Engine electrical systems).

2. Follow the procedures in paragraphs 3 through 6 (see above for M612).

3. Unlock and disconnect the contact connectors (5, 6 and 7) on the CDI control module (N39/2), - access to connector (6) is available after disconnecting connector (6).

4. Disconnect the connector (8).

5. Release the engine wiring harness (9) through the passage in the body panel, being careful not to damage the insulation.

6. Disconnect the ground bus (10).

7. Release the lock (11).

8. Unscrew the output connector of circuit 30 of the preheating system (N14/2x3).

9. After releasing the bayonet lock, disconnect the central contact connector of the electrical wiring (X22/2) AT.

10. Unbolt the transmission ground bus (W49) from the frame.

11. Installation is carried out in the reverse order - if the corresponding configuration (code ET2) deactivate the service mode of the TELE AID system (see Section Activation/deactivation of the service mode of the TELE AID emergency call system).

12. Finally, read the DTC codes and clear the on-board diagnostic system memory using the STAR DIAGNOSIS scanner (6511 1801 00) (See Chapter Engine electrical systems).

Removal the power unit

Note: All self-locking fasteners must be replaced.

Petrol models

463.250/249 (G320 / 500 with M112. 945/113. 962 engines)

1. Drive the vehicle onto a lift (see Section Jacking/lifting a car and transporting it in case of an accident).

2. Remove the engine trim panel with built-in air cleaner (2), - lift the panel up and separate it from the cylinder head covers (see Chapter Fuel and exhaust systems).

3. Disconnect the air intake hoses at the top of the wheel arches.

4. Disconnect the ground wire from the battery (see Chapter Engine electrical systems).

5. Remove the lower boot (1) of the engine compartment.

6. Drain the cooling system (see Chapter Routine care and maintenance or Cooling, heating, ventilation and air conditioning systems).

7. Drain the engine oil (see Chapter Routine care and maintenance).

8. Remove the fan with viscous coupling (3) and the fan assembly casing (7) (see Chapter Cooling, heating, ventilation and air conditioning systems).

9. Remove the cooling system radiator (see Chapter Cooling, heating, ventilation and air conditioning systems).

10. Install the air conditioning radiator/condenser protection screen (a metal or plastic sheet measuring approximately 400x680x1 mm).

11. Disconnect the engine wiring (see above).

12. Disconnect the coolant lines (9) from the water pump assembly.

13. Remove the hot-wire air mass (MAF) sensor (B2/5) built into the intake air duct (see Chapter Fuel and exhaust systems).

14. Disconnect the vacuum line (5) from the brake booster servo assembly at the rear of the intake manifold.

15. Disconnect the vacuum line (6) from the intake manifold.

16. Pump out the power steering fluid from the steering pump reservoir (11).

17. Disconnect the return (12) and pressure (13) hydraulic lines from the steering pump assembly (11) - immediately seal the open ends of the lines and fittings with pre-prepared plugs.

18. Release the pressure in the fuel system through the service valve (see Chapter Fuel and exhaust systems), then disconnect the fuel line (4) from the fuel line - get ready to collect the spilled fuel.

19. Remove the cooling tract line (14).

20. Remove the accessory drive belt (15) (see Section Replacement of the auxiliary drive belt and elements of its tensioning mechanism), - to fix the tensioner you will need a rod with a diameter of 5 mm.

21. Disconnect the hoses (17) from the oil lines (18) - immediately seal the open ends of the lines with the plugs prepared in advance.

22. Remove the exhaust system assembly (see Chapter Fuel and exhaust systems) (except models 463.249).

Note: If the engine is removed due to failure, the catalytic converters (23) must be checked for the presence of chips, which must be removed before installation.

23. Unbolt the power unit suspension support (20) from the frame.

24. Raise the unit by lifting it from the front lifting eye, making sure that no components are pinched.

25. Unbolt the K/V compressor (21) from the timing drive cover and, without disconnecting the refrigeration lines, move it to the side.

26. Lower the power unit, again making sure that no components are pinched.

27. Unbolt the cardan shaft (24) from the transmission connecting flange - the shaft mounting bolts must be replaced without fail.

28. Remove the clamp (25) and disconnect the shift rod (26) from the transmission.

29. Remove the frame cross member (27) complete with the rear transmission support (see Section Removal and installation the powertrain suspension supports) (except models 463.249).

30. Attach the rigging straps to both eyes of the power unit.

31. Lower the unit and, pushing it backwards, remove it from the engine compartment.

32. Installation is carried out in reverse order.

33. Check the unit for signs of developing coolant leaks.

Note: If the cylinder head gaskets have been replaced, the engine should first be warmed up to normal operating temperature.

34. Check the ATF level and make adjustments if necessary (see Chapter Routine care and maintenance).

35. Start the engine and check it for signs of developing fluid leaks.

36. Finally, read the DTC codes and clear the on-board diagnostic system memory using the STAR DIAGNOSIS scanner (6511 1801 00) (See Chapter Engine electrical systems).

463.246 (G55 AMG with M113.982 engine)

1. The corresponding illustrative material is presented in the illustrations Preparing to remove the power unit on gasoline models (1 of 2), Preparing to remove the power unit on gasoline models (2 of 2), Details of installing the power unit on gasoline models, to which all references in the text refer.

2. Open the hood and fix it in a vertical position.

3. Discharge the air conditioning system - contact specialists.

4. Remove the engine trim panel with built-in air cleaner (2), - lift the panel up and separate it from the cylinder head covers (see Chapter Fuel and exhaust systems).

5. Disconnect the air intake hoses at the top of the wheel arches.

6. Disconnect the ground wire from the battery (see Chapter Engine electrical systems).

7. Remove the decorative radiator grille (see Chapter Body).

8. Remove the upper front cross member.

9. Disconnect the communication lines and remove the auxiliary fan.

10. Disconnect the lines from the A/C system cooler - immediately seal the open ends of the lines with the plugs prepared in advance.

11. Remove the A/C cooler.

12. Remove the lower boot (1) of the engine compartment (see accompanying illustration - Installation details of the lower engine compartment protection boot on G55 AMG models).



13. Drain the cooling system (see Chapter Routine care and maintenance).

14. Drain the engine oil (see Chapter Routine care and maintenance).

15. Disconnect the oil pipes from the oil-water heat exchanger (see accompanying illustration - Fastening details of oil pipes to the oil-water heat exchanger of the compartment on G55 AMG models)



16. Perform the procedures of paragraphs 8, 9 and 11 through 19 for 463.250/249 (G320 / 500 with M112. 945/113. 9620 engines).

17. Remove the vacuum line from the inlet bulkhead to the purge valve.

18. Disconnect the refrigeration lines from the A/C compressor.

19. Disconnect the hoses (17) from the oil lines (18) going to the ATF cooler - immediately seal the open ends of the lines with the plugs prepared in advance.

20. Perform the procedures of paragraphs 22, 23, 27 and 28 for 463.250/249 (G320 / 500 with M112. 945/113. 9620 engines).

21. Remove the two bolts and remove the transmission support from the frame cross member.

22. Attach the rigging straps to both eyes of the power unit.

23. Lift the front of the unit and remove it from the engine compartment.

24. Installation is carried out in reverse order.

25. Fill the air conditioning system and check it for signs of developing leaks.

26. Then proceed in accordance with the instructions given in paragraphs 33 through 36 for 463.250/249 (G320 / 500 with M112. 945/113. 9620 engines).

Diesel models

463.323 (G270 CDI with 612.965 engine)

1. On models with the corresponding configuration (code ET2), activate the service mode of the TELE AID emergency call system (see Section Activation/deactivation of the service mode of the TELE AID emergency call system).

2. Disconnect the ground wire from the battery (see Chapter Engine electrical systems).

3. Remove the trim panels from the cylinder head cover.

4. Drive the car onto a lift, or jack up the car and place it on supports (see Section Jacking/lifting a car and transporting it in case of an accident).

5. Remove the lower engine compartment boots.

6. Drain the cooling system (see Chapter Routine care and maintenance).

7. Remove the air cleaner (1) (see Chapter Fuel and exhaust systems).

8. Remove the air intake tract resonator chamber with the water collector (2) (see Chapter Fuel and exhaust systems).

9. Remove the primary catalytic converter (see Chapter Fuel and exhaust systems).

10. Remove the viscous coupling of the cooling system fan drive (see Chapter Cooling, heating, ventilation and air conditioning systems).

11. Remove the radiator (see Chapter Cooling, heating, ventilation and air conditioning systems).

12. On models equipped with the A/C system (code H02), install the air conditioning radiator/condenser protection screen (a metal or plastic sheet measuring approximately 400x680x1 mm).

13. Disconnect the power steering fluid cooling line (4).

14. On models equipped with the A/C system (code H02), remove the auxiliary cooling fan (5).

15. Remove the low-temperature cooler (6) (see Chapter Cooling, heating, ventilation and air conditioning systems).

16. Remove the intercooler (Intercooler) (7) turbocharging systems (see Chapter Fuel and exhaust systems).

17. Disconnect the cooling system hoses (8 and 9).

18. Loosen the two nuts and, without disconnecting them from the nipple connectors, separate the tubes (10) from the frame cross pipe.

19. Remove the heat shield (11) of the boost air cooling circulation pump (M44), then remove the pump assembly itself.

20. Remove the coolant circulation pump (M13) (see Chapter Cooling, heating, ventilation and air conditioning systems).

21. Disconnect the pressure line (12) from the steering pump (13), - prepare replacement sealing rings for the hollow bolt of the nipple connector.

22. Disconnect the connector (14) at the preheating system output (N14/2).

23. Disconnect the right (15) and left (16) vacuum lines from the turbocharger and mixing chamber respectively.

24. Disconnect the engine vacuum line (17) from the brake booster servo line (18).

25. Disconnect the engine wiring (see above).

26. Disconnect the cooling line (19) from the fuel preheater (20).

27. Release the fuel lines (21) on the frame in the left front wheel arch.

28. Remove the transmission output speed sensor (B49), release the wiring from the ATF filler neck support bracket, - prepare a replacement gasket and bandage.

29. Remove the latch (23) and disconnect the shift rod (22) from the transmission.

Note: When installing a new rod, do not forget to adjust it (see Chapter Automatic transmission).

30. Attach lifting straps to both eyes of the power unit and hang the latter on the winch, making sure that no lines or components are pinched.

31. On models with the appropriate configuration (code H02), disconnect the electrical wiring from the A/C compressor, then unbolt the compressor and move it to the side without disconnecting the refrigeration lines.

32. Loosen the fastening nuts (27) and disconnect the cardan shaft (25) from the connecting flange (26) of the transmission - the nuts must be replaced without fail - if necessary, loosen the fasteners and tilt the transmission slightly.

Note: When installing the shaft in place, ensure that it passes between the support flanges of the distribution block and the automatic transmission.

33. Lift the engine and remove it from the engine compartment through the top.

34. Support the transmission from below with a suitable jack - to remove the cross member with the rear support of the powertrain suspension installed on it, the transmission will have to be raised.

35. Remove the rear support of the powertrain suspension (see Section Removal and installation the powertrain suspension supports),

36. Remove the bolts (28 and 29) securing the front powertrain suspension supports to the frame.

37. Remove the ATF cooler line support brackets from the right frame rail.

38. Disconnect the ventilation hose from the top of the AT crankcase - the engine will have to be pulled forward slightly.

39. Lower the rear of the power unit and, pushing it forward, remove it from the engine compartment, making sure that no suspension components or body panels are damaged.

40. Installation is carried out in the reverse order, if the corresponding equipment is installed (code service mode) deactivate TELE AID systems (see Section Activation/deactivation of the service mode of the TELE AID emergency call system).

41. Fill and "bleed" the power steering system (see Chapter Suspension and steering).

42. Bleed the cooling system (see Chapter Routine care and maintenance).

43. Then proceed in accordance with the instructions given in paragraphs 33 through 36 for 463.250/249 (G320 / 500 with M112. 945/113. 9620 engines).

463.333 (G270 CDI with engine 628.962)

1. Disconnect the ground wire from the battery (see Chapter Engine electrical systems).

2. Open the hood and fix it in a vertical position.

3. Remove the lower engine compartment protection panels.

4. Drain the cooling system (see Chapter Cooling, heating, ventilation and air conditioning systems).

5. Remove the air cleaner (1) (see Chapter Fuel and exhaust systems).

6. Remove the MAF sensors built into the left and right intake duct assemblies (B2/6 and B2/7) (See Chapter Fuel and exhaust systems).

7. Remove the air intake ducts (2) from the left and right wing mudguards (see Chapter Fuel and exhaust systems).

8. Disconnect the vacuum line (3) of the inlet port shut-off valve from the tee (4).

9. By squeezing the locks of the nipple connector (5), disconnect the vacuum lines (6 and 6a).

10. Remove the air intake tract resonator chamber with the water collector (7) (see Chapter Fuel and exhaust systems).

11. Disconnect the engine wiring (see above).

12. Remove the front grille (10) (see Chapter Body).

13. Remove the fan shroud (11) (see Chapter Cooling, heating, ventilation and air conditioning systems).

14. Disconnect the ventilation lines (12 and 13) of the cooling tract.

15. Remove the condenser (14) together with the radiator (15) (see Chapter Cooling, heating, ventilation and air conditioning systems).

16. Remove the low-temperature cooler (16) (see Chapter Cooling, heating, ventilation and air conditioning systems).

17. Disconnect the cooling lines (17 and 18) - immediately seal the open ends of the lines with the plugs prepared in advance.

18. Remove the cooling system circulation pump (M13).

19. Disconnect the cooling line (19) from the charge air cooling circulation pump (M44).

20. Release the right hood cable.

21. Pump out the working fluid from the steering pump reservoir (20).

22. Disconnect the pressure (21) and return (22) lines from the steering pump (20)/its reservoir, respectively - immediately seal the open ends of the lines and fittings with the plugs prepared in advance.

23. Disconnect the ATF line (23) from the transmission fluid cooler (24).

24. Unscrew the nut (25).

25. Disconnect the inlet compressor line (26) from the expansion valve (27) of the air conditioning system, immediately seal the open ends of the lines and fittings with the plugs prepared in advance, and prepare replacement sealing elements.

26. After first pinching, disconnect the fuel supply (9) and return (8) lines - prepare to collect any spilled fuel.

27. Remove the transmission output speed sensor (B49).

28. Separate the sensor assembly (B49) with the cable (29) from the engine, release the cable from the support plates (30) of the oil filler neck (31), remove the tie bandages.

29. Remove the exhaust system without the final muffler (see Chapter Fuel and exhaust systems).

30. Unbolt the cardan shaft (32) from the transmission connecting flange (33), loosen the fasteners if necessary and tilt the transmission slightly.

Note: When installing the shaft in place, ensure that it passes between the support flanges of the distribution block and the automatic transmission.

31. Remove the latch (36) and disconnect the shift rod (35) from the transmission.

Note: When installing a new rod, do not forget to adjust it (see Chapter Automatic transmission).

32. Attach lifting straps to both eyes of the power unit and hang the latter on the winch, making sure that no lines or components are pinched.

33. Support the transmission from below with a suitable jack and lift it slightly to remove the rear powertrain mount.

34. Remove the rear powertrain suspension support.

35. Unscrew the bolts (37 and 38) securing the left (37) and right powertrain suspension supports to the frame.

36. Lower the rear of the unit and, pushing it forward, remove it from the engine compartment, making sure that no suspension components or body panels are damaged.

37. Installation is carried out in reverse order.

38. Fill and "bleed" the power steering system (see Chapter Suspension and steering).

39. Then proceed in accordance with the instructions given in paragraphs 33 through 36 for 463.250/249 (G320 / 500 with M112. 945/113. 9620 engines).