Piper SARATOGA PA-32-301 Maintenance Manual page 177

PIPER AIRCRAFT
PA-32-301/301T
MAINTENANCE MANUAL
SERVICE PROCEDURES.
Since the alternator and regulator are designed for use on only one polarity system. the following
precautions must be observed when testing or servicing the electrical system. Failure to observe these
precautions will result in serious damage to the electrical equipment.
1. Disconnect the battery before connecting or disconnecting test instruments (except voltmeter) or
before removing or replacing any unit or wiring. Accidental grounding or shorting at the regulator. alternator,
ammeter or accessories, will cause severe damage to the units and/or wiring.
2. The alternator must not be operated on open circuit with the rotor winding energized.
3. Do not attempt to polarize the alternator. No polarization is required. Any attempt to do so may
result in damage to the alternator, regulator or circuits.
4. Grounding of the alternator output terminal may damage the alternator and/or circuit and
components.
5. Reversed battery connections may damage the rectifiers, wiring or other components of the charging
system. Battery polarity should be checked with a voltmeter before connecting the battery. Most aircraft are
negative ground.
6. If a booster battery or fast charger is used, its polarity must be connected correctly to prevent damage
to the electrical system components.
OVERHAUL OF ALTERNATOR.
When repairing the alternator, complete disassembly may not be required. In some cases it will only be
necessary to perform those operations which are required to effect the repair. However. in this section. the
complete overhaul is covered step-by-step to provide detailed information on each operation. In actual service
practice, these operations may be used as required.
DISASSEMBLY OF ALTERNATOR.
1. Remove the two Number 10-24 screws holding the brush holder assembly in the slip ring end head.
Remove the brush and holder assembly from the end head.
2. Remove the safety wire from the through bolts. Hold the pulley with a strap wrench and remove the
pulley nut. The pulley must be removed with a puller. Remove the fan, woodruff key and spacer from the shaft.
3. Remove the four through bolts and tap the drive end head lightly to separate the drive end head and
rotor. as a unit. from the stator and slip ring end head.
4. Remove the nuts, lock washers, flat washers and insulators from the output and auxiliar terminal
studs. Note carefully the correct assembly of the insulator washers and bushings. Using the special tools shown
in Figure 24-4. support the end head and press out the three negative rectifiers. The end head can now be
separated from the stator assembly.
5. To remove the slip ring end bearing and grease seal, it will be necessary to have a hook type or impact
type bearing puller as shown in Figure 24-3. Do not remove the bearing unless replacement is necessary.
- NOTE -
The inner race of the slip ring end bering is pressed onto the rotor
shaft. When bearing replacement is necessary, always replace the
complete bearing assembly, including the inner race.
EFFECTIVITY: PRESTOLITE
24-31-05
Page 24-12
Revised: August 23, 1982
1H9