The alternating current generator (alternator) supplies a continuous output of electrical energy at all engine speeds. The alternator generates electrical energy and recharges the battery by supplying it with electrical current. This unit consists of four main assemblies: two end frame assemblies, a rotor assembly, and a stator assembly. The rotor assembly is supported in the drive end frame by a ball bearing and at the other end by a roller bearing. These bearings are lubricated during assembly and require no maintenance. There are six diodes in the end frame assembly. These diodes are electrical check valves that also change the alternating current developed within the stator windings to a direct current (DC) at the output (BAT) terminal. Three of these diodes are negative and are mounted flush with the end frame while the other three are positive and are mounted into a strip called a heat sink. The positive diodes are easily identified as the ones within small cavities or depressions.
To prevent serious damage to the alternator and the rest of the charging system, the following precautions must be observed:
REMOVAL & INSTALLATION
See Figures 1 through 5
- Disconnect the negative battery cable to prevent diode damage.
- Tag and disconnect the alternator wiring.
- Remove the alternator brace bolt. If the car is equipped with power steering, loosen the pump brace and mount nuts. Detach the drive belt(s).
- Support the alternator and remove the mount bolt(s). Remove the unit from the vehicle.
To install, reverse the removal procedure. Alternator belt tension is quite critical. A belt that is too tight may cause alternator bearing failure; one that is too loose will cause a gradual battery discharge. For details on correct belt adjustment, see Drive Belts in Repair Guide .