Chevrolet Corvette 1963 Repair & Tune-Up Manual page 80

ground), start the engine and run at 1,500-
2,000 rpm with all lights and electrical acces-
sories turned on. If the voltmeter reads 12.8
volts or greater, the alternator is good and no
further checks need be made. If the voltme-
ter reads less than 12.8 volts, ground the field
winding by inserting a screwdriver into the
test hole in the end frame.
CAUTION: Do not force the tab more than
% in. into the end frame.
a. If voltage increases to 13 volts or
more, the regulator unit is defective;
b. If voltage does not increase signifi
cantly, the generator is defective.
High Charging Rate Diagnosis
1. With the battery fully charged, connect
a voltmeter between alternator terminal No.
2 and ground. If the reading is zero, No. 2
circuit from the battery is open.
2. If No. 2 circuit is OK, but an obvious
overcharging condition still exists, proceed as
follows:
a. Remove the alternator and separate
the end frames;
b. Connect a low-range ohmmeter be
tween the brush lead clip arid the end frame
(Test 1), then reverse the connections. If
both readings are zero, either the brush
lead clip is grounded or the regulator is de
fective. A grounded brush lead clip can be
due to damaged insulating sleeve or omis
sion of the insulating washer.
REMOVAL AND INSTALLATION
1. Disconnect the negative battery cable
at the battery; this will prevent damaging the
alternator diodes.
2. Disconnect the wiring from the rear of
the alternator (bolt-on and push-in connec
tors).
3. Loosen the lower alternator bolt and re
move the upper (adjustment) bolt. Slip the
drive belt off of the pulley.
4. Remove the pivot bolt and lift the alter
nator out of its mounting brackets.
5. Installation of the alternator is the re
verse of the previous steps. Adjust the drive
belt to the proper tension.
DISASSEMBLY AND ASSEMBLY
Externally Regulated Type—Except
"Perforated Case" Models
Remove the pulley by positioning a box-end
wrench over the pulley retaining nut and in-
5
serting a /i6 in. alien wrench in the shaft to
ENGINE AND ENGINE REBUILDING
prevent it from turning. Unbolt the retaining
nut and slide it off the pulley. Disconnect the
battery ground strap to prevent diode dam-
age and remove the generator. On the 6.2 in.
perforated case generator, remove the blade-
connector retaining nuts and remove the
connectors. Slip the indicator light relay from
the terminal post, then back out die retaining
screws, and remove the brush holder. Leave
the capacitor attached to the generator. Re-
move the four, long, case bolts and separate
the end frame and rotor assembly from the
stator assembly. Cover the slip ring and bear-
ing with tape to prevent contamination.
Remove the rotor from the end frame. Ex-
tract the retainer plate screws and remove the
retainer plate and the end frame bearing. Re-
move the three attaching screws and separate
the stator from the end frame. Remove the
heat sink.
Wash all metal parts with the exception of
the stator and rotor assemblies. The rotor slip
rings may be cleaned with 400 grain polish-
ing cloth. It is a good idea to rotate the rotor
while doing this to guard against rubbing flat
spots on the slip rings. Maximum out-of-round
tolerance for sh'p rings is 01001 in. Remove as
little metal as possible when truing on a lathe.
Polish with 400 grain cloth and blow dry. To
assemble the alternator: Attach the slip-ring
end frame to the stator assembly and
position the diode connectors above the
diode, relay, and stator leads. Tighten the
terminal nuts, then slide the front end frame
over the rotor. Slide on the spacer, pulley,
washer, and nut, and torque the shaft to 50-
60 ft. Ibs. Attach the slip-ring end frame and
stator to the rotor and drive end frame
assembly and insert and tighten the thru-
bolts.
Externally Regulated Type—"Perforated
Case" Models
1. Mount the alternator in a vise, clamp
ing the drive end mounting flange length
wise.
2. Remove the two screws which secure
the cover to the brush holder and remove the
cover.
3. Remove the nut which retains the in
dicator light wire to the bkde connector post.
Disconnect the wire from the connector post.
4. Remove the two brush holder assem
bly attaching screws and remove the brush
holder.
NOTE: The capacitor lead is connected in-
side the alternator; the capacitor must stay
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