Removal and installation of the Mercedes-Benz W203 generator

Tool:

• torque wrench
• Jack
• Support legs

Parts and consumables:

• Cooling fluid

The vehicle has a three-phase alternator. Depending on the model and equipment, generators of various capacities can be installed.

Notes:

If electrical appliances with a high consumption of electricity are subsequently installed on the vehicle, it is necessary to check whether the power of the existing alternator is sufficient. If necessary, install a new generator of higher power.

The alternating voltage created by the generator is converted by the rectifier diodes into a constant voltage, which charges the battery. The regulator changes the charging current in such a way that the operating voltage is kept constant regardless of the speed.

Notes:

The generator can be replaced. Damaged generator when buying a repaired or new generator is taken into account. Therefore, take the failed generator with you.

Petrol engines 111, 112 

Withdrawal

The cabin air filter box must first be removed.

1. Disconnect the negative (-) battery cable with the ignition off. 

Notes:

Before disconnecting the cable, find out the security code of the radio, if any.

Do not connect an auxiliary power supply.

2. Engine 111: Remove the air filter housing.

3. Engine 112: Remove the air intake duct on the passenger's side.

4. Remove the V-belt.

5. Remove the protective cover and disconnect the thick wire from the terminal.

6. Disconnect the wire from the terminal.

1 - B+ wire;

2 - D+ wire:

3 - mounting bolts;

4 - protective cover.

7. Turn out bolts of fastening. Remove the top bolt spacer and lift the alternator up out of the engine compartment.

Installation

1. Install the generator in place and secure it with a torque of 42Nm.

Notes:

Pay attention to the remote bushing of the upper mounting bolt.

2. Fasten the wire to the generator terminal with the force specified in the Specifications.

3. Put the protective cap on the terminal.

4. Fasten the wire to the generator with a torque of 5 Nm.

5. Put on the V-belt.

6. Engine 111: Install the air filter housing.

7. Engine 112: Install the air intake duct.

8. Attach a cable of weight (-) of the storage battery at the switched off ignition. Install the cabin air filter box. If necessary, enter the radio code and set the time on the clock.

Diesel engines

Withdrawal

1. Disconnect the negative (-) battery cable with the ignition off. The cabin air filter box must first be removed.

Notes:

Before disconnecting the cable, find out the security code of the radio, if any.

Do not connect an auxiliary power supply.

2. Remove the engine cover.

3. Remove the V-belt.

4. Remove the air intake duct and hose from the front passenger side.

5. Disconnect the clamp and charge air hose from the turbocharger pipe.

6. Turn out 3 bolts of fastening and remove a pipe.

7. Raise and place the front of the vehicle on stands.

8. Remove the bottom cover.

9. Drain the liquid from the radiator.

10. Disconnect the coolant supply pipe from the generator.

11. Remove the front suspension stabilizer bar.

12. Remove the protective cover and disconnect the thick wire from the terminal.

13. Disconnect the wire from the terminal.

14. Turn out 2 bolts of fastening and take away a pipeline of a high pressure of a steering.

15. Turn out 3 bolts of fastening and remove the holder.

16. Turn out bolts of fastening and take out the generator down from an impellent compartment.

Installation

1. Install the generator in place and fix it with bolts with a torque of 20 Nm. At the same time, replace the gasket between the flange of the radiator housing and the engine crankcase.

2. Fix the pipeline of a supply of a cooling liquid on the generator, at the same time replace a sealing ring.

3. Attach the holder.

4. Attach the high pressure steering line.

5. Fix the wire with a torque of 14Nm on the generator and put on the protective cap on the terminal.

6. Attach the wire to the generator.

7. Replace the stabilizer.

8. Fill the system with coolant.

9. Install the bottom cover.

10. Lower the car on wheels.

11. Attach the charge air pipe to the turbocharger and connect the hose.

12. Reinstall the air intake duct and hose.

13. Put on the V-belt.

14. Install the engine cover.

15. Attach a cable of weight (-) of the storage battery at the switched off ignition. Install the cabin air filter box. If necessary, enter the radio code and set the time on the clock.

The article is missing:

• Tool photo
• Photo of parts and consumables
• High-quality repair photos

Source:  http://www.auto-knigi.com/model/mb_c/7_4_7/