d. Bearing and Seals: Whenever the alternator is overhauled, new bearings and oil or grease seals are
recommended, even though the bearing and seals appear to be in good condition. A faulty seal can cause an
alternator to fail within a very short period of time.
11-12. ASSEMBLY OF ALTERNATOR.
a. Press the ball bearing into the drive end head using a flat block approximately two inch square so that the
pressure is exerted on the outer race of the bearing. Install the retainer plate. With the snap ring and retainer cup
in place on the rotor shaft, use a tool that fits over the shaft and against the inner bearing race, and press until the
inner bearing race is against the snap ring retainer cup. (Refer to Figure 11-10).
b. Carefully install the rectifier in the slip ring end head or rectifier mounting plate by supporting the unit and
using the special tools illustrated in Figure 11-11.
—CAUTION—
Use an arbor press, do not hammer. Reconnect the stator leads to the
rectifier. When soldering these connections use pliers as a heat sink on
the lead between the solder joint and the rectifier. Too much heat will
damage the rectifier.
c. Reassemble the rectifier mounting plate studs and insulators, making sure they are in the correct order.
d. After the slip ring end head is completely assembled, the stator and rectifier leads must be secured to the
rectifier mounting plate with epoxy. Make sure the stator leads are positioned so that they do not interfere with
the rotor.
e. Install the slip ring end bearing and oil seal. Make sure the lip of the oil seal is toward the bearing. Stake
Figure 11-8 Testing Rotor for Grounds Figure 11-9 Testing Rotor for Shorts
366
265
AMMETER
ROTOR
VOLTMETER
BATTERY
REOSTAT
PIPER AIRCRAFT
PA-28-161 CADET
AIRPLANE MAINTENANCE MANUAL
Issued: FEBRUARY. 28, 1989
ELECTRICAL SYSTEM
2D4