You will need: 13mm and 24mm socket heads, flat- and Phillips-head screwdrivers, punch, soldering iron, rotor bearing puller, hammer, tester.
1. Remove the generator from the vehicle (see "Removal and installation the generator").
2. Mark the relative positions of the generator parts.
3. Clamp the generator pulley in a vice, having first placed some pads under it or wound an old belt, and unscrew the pulley mounting nut.
4. Remove the generator pulley from the vice and remove the pulley from the rotor shaft.
Note: The generator pulley is secured against turning on the rotor shaft only by friction forces after tightening the fastening nut to the required torque. There is no key in the connection.
5. Unscrew the nut…
6. …and, using a screwdriver, remove the generator terminal.
7. Remove the four clamping screws…
8. ... using a screwdriver, remove the front cover of the generator and take out the anchor.
9. Remove the spacer ring from the rotor shaft.
10. Unsolder the three stator winding leads from the rectifier unit and remove the stator.
Note: When desoldering, it is more convenient to use a special device for removing molten solder.
11. From the inside of the cover on the side of the contact rings, unscrew the three fastening screws and remove the brush holder assembled with the rectifier unit and voltage regulator.
Note: The stator terminals must already be unsoldered from the rectifier unit during the stator removal process (see item 10).
12. Inspect the generator cover from the drive side. If, when rotating the bearing, you feel play between the races, the inner race rolls or jams, the protective cuffs are damaged or there are signs of grease leakage, replace the bearing. If cracks are found in the cover, especially in the places where the generator is attached, replace the cover.
13. To replace the front rotor bearing, remove the four screws securing the pressure plate…
14. …and remove the plate.
15. Press the bearing out of the cover.
16. Using a mandrel of suitable diameter, press the new bearing into the cover, applying force to the outer race of the bearing.
17. Check the ease of rotation of the bearing from the contact ring side. If, when rotating the bearing, there is play between the races, the race rolls or jams, the protective cuffs are damaged or there are signs of grease leakage, replace the bearing. If cracks are found in the cover, replace the cover with a new one.
18. Press the bearing off the rotor shaft and install a new one, applying force to the inner race of the bearing with a mandrel of a suitable diameter.
19. Check the rotor winding resistance with a tester by connecting it to the contact rings. The resistance should be about 3–5 Ohms. If the tester shows infinity, then there is a break in the windings and the rotor needs to be replaced.
20. Check the rotor winding short circuit to ground. To do this, connect one tester probe to the rotor pole piece and the other one to the contact rings in turn. The measured resistance should be infinitely large, otherwise replace the rotor.
21. Check the stator windings for breakage by measuring the resistance between all winding terminals one by one with a tester. If the measured resistance tends to infinity, the stator must be replaced.
22. Connect the tester probes to the stator housing and to each winding terminal in turn. The measured resistance should be very high (tend to infinity). Otherwise, replace the stator.
23. Check the rectifier unit. To do this, connect one probe of the tester to the terminal of the phase winding of the stator, and the second probe to the air radiator of the positive diodes. By changing the tester probes, measure the resistance. If the tester readings are the same in both cases, the rectifier unit is faulty and requires replacement.
24. Check the negative diodes in the same way.
25. Check the protrusion of the brushes in a free state. If the size is less than 3 mm, replace the brushes or the brush holder assembly.
Note: To replace the brushes, you will need to unsolder their wires from the brush holder terminals.
26. Assemble the generator in the reverse order of removal, orienting the generator and stator housing covers according to the previously made marks.
Note: Before installing the cover on the rotor slip ring side, recess the brushes and secure them in this position by inserting a pin (e.g. an unbent paper clip) into the cover hole. Remove the pin after assembly.