Chevrolet 1977 light duty truck, Руководство по обслуживанию

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two readings taken for each diode.
N OTE:
The diodes are not replaced individually. The
entire rectifier bridge is replaced if one or m ore diodes
are defective.
CAUTION: D o n o t use high voltage to check the
rectifier bridge, such as a 110 volt test lamp.
Voltage Reg./Brush Lead Clip Check (Fig. 6D-5C)
Connect an ohm m eter from the brush lead clip to the
end frame as shown in Step 1, Figure 6D-7C. Then reverse
lead connections. If both readings are zero, either the brush
lead clip is grounded or the regulator is defective.
A grounded brush lead clip can result from omission of
the insulating washer, omission of the insulating sleeve on the
screw, or a damaged insulating sleeve. Remove the screw and
inspect the sleeve. If it is satisfactory, replace the regulator
unit.
R E P A IR S
Brush Holder and Regulator Replacement (Fig.
6D-5C)
1. If not previously removed, remove the three stator
lead attaching nuts, the stator, diode trio brush lead screw
and diode trio from the end frame.
2. Remove the remaining two screws from the brush
holder and regulator and remove these units from the end
frame.
N OTE: The two screws retaining the brush clips have
insulating washers over the tops of the brush clips and
special insulating sleeves over the screw body above the
threads. If they are damaged or missing a ground will
result causing uncontrolled or no output.
3. Replace defective unit and reassemble using reverse
of removal procedures.
N O TE: The screw nearest regulator term inals does not
have an insulating washer, but may or may not have an
insulating sleeve.
Slip Ring Servicing
If the slip rings are dirty, they may be cleaned and
finished with 400 grain or finer polishing cloth. Spin the
rotor, and hold the polishing cloth against the slip rings until
they are clean.
CAUTION: The rotor m u st be rotated in order that
the slip rings will be cleaned evenly. Cleaning the
slip rings b y ha n d w ithout spinning the rotor m ay
result in flat spots on the slip rings, causing brush
noise.
Slip rings which are rough or out of round should be
trued in a lathe to .002 inch maximum indicator reading.
Remove only enough m aterial to m ake the rings smooth and
round. Finish with 400 grain or finer polishing cloth and blow
away all dust.
Drive End Frame-Bearing Replacement/
Lubrication
1. The drive end frame bearing can be removed by
detaching the retainer plate bolts and separating retainer
plate and seal assembly from end frame, and then pressing
bearing out using suitable tube or pipe on outer race.
2. Refill bearing one-quarter full with Delco-Remy No.
1948791 grease or equivalent. Do not overfill.
3. Press bearing into end frame using tube or pipe as in
Step 1 with bearing and slinger assembled as shown in Figure
6D-8C.
Fig. 6 D - 1 4C ~D rive End B e a rin g Cross S e ctio n
4. Install retainer plate. Use new retainer plate if felt seal
is hardened or excessively worn.
NOTE: Stake retainer plate bolts to plate.
Slip Ring End Frame-Bearing Replacement
1. Replace the bearing if the grease supply is exhausted.
Make no attem pt to re-lubricate and reuse the bearing.
2. Press out from outside of housing, using suitable tool
over outer race of bearing.
3. To install, place a flat plate over the bearing and press
in from outside of housing until bearing is flush with the
outside of the end frame. Support inside of end frame around
bearing bore with a suitable tool to prevent distortion. Use
extreme care to avoid misalignment.
4. Install new seal whenever bearing is replaced. Lightly
coat the seal lip with oil and press seal into the end frame
with the seal lip toward the inside of the end frame.
R E A S S E M B L Y
1. Install rotor in drive end frame and attach spacer, fan,
pulley, washer, and nut.
2. Using adapter J-2 1501, insert an alien wrench into hex
shaped hole at end of shaft and torque the shaft nut to 40-50
ft. lbs. (fig. 6D-9C).
3. Install capacitor and retaining screw in slip ring end
frame.
4. Position brush holder and regulator assemblies in end
frame and install two retaining screws.
N OTE: The two screws retaining the brush clips have
insulating washers over the top of the brush clips and
special insulating sleeves over the screw body above the
threads. If the third screw does not have an insulating
sleeve, it must not be interchanged with either o f the
other two screws.
5. Position rectifier bridge to end frame. Install attaching
screw and the "BAT" term inal screw. Connect capacitor lead
to bridge.
6. Position diode trio on rectifier bridge term inal and