SkyTrak 6036 Service Manual - Manual (Page 221)

Section 10. Electrical System
Model 6036 S/N 9B0499 and Before 10-27
2. A short-circuit in the stator windings is difficult
to locate without laboratory test equipment due
to the low resistance of the windings. How-
ever, if all other electrical checks are normal
and the alternator fails to supply rated output,
shorted stator windings or an open delta
winding are indicated. Also, a shorted stator
can cause the indicator lamp to be on with the
engine at low speed. Check the regulator in the
next paragraph before replacing stator.
i. Brush Holder and Regulator Replacement
IMPORTANT: To determine if the regulator is
defective, use an approved regulator tester.
After removing the three attaching nuts, and diode
trio screw, Fig. 10.30, the brush holder and regula-
tor may be replaced by removing the two remaining
screws. Note the two insulators located over the
top of the brush clips in Fig. 10.30 and that these
two screws have special insulating sleeves over
the screw body above the threads. The third
mounting screw may or may not have an insulating
sleeve. If not, this screw must not be interchanged
with either one of the other two screws, as a ground
may result, causing no output or uncontrolled
alternator output.
j. 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.
IMPORTANT: The rotor must be rotated in order to
clean the slip rings evenly. Cleaning the slip rings
by hand without spinning the rotor may 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 0.002" (0.05 mm) maximum
indicator reading. Remove only enough material to
make the rings smooth and round. Finish with 400
grain or finer polishing cloth and blow away all dust.
Fig. 10.34 Drive End Bearing Assembly
(Some Models Use a Flat Washer Instead of a Slinger)
k. Bearing Replacement and Lubrication
The bearing in the drive end frame can be removed
by detaching the retainer plate screws, and then
pressing the bearing from the end frame, refer to
Fig. 10.34. If the bearing is in satisfactory condi-
tion, it may be reused, and it should be filled one-
quarter full with Delco Remy Lubricant No. 1948791
before reassembly.
Fig. 10.35 Drive End Bearing Assembly,
Late Production, All Series
IMPORTANT: Do not overfill, as this may cause
the bearing to overheat, and use only 1948791
Lubricant. The bearing in Fig. 10.35 is sealed on
both sides; lubrication is not required.
To install a new bearing, press in with a tube or
collar that just fits over the outer race, with the
bearing assembled into the end frame as shown in
Fig. 10.34. Install a new retainer plate if the felt
seal in the retainer plate is hardened or excessively
worn. Fill the cavity between the retainer plate and
bearing with 1948791 Lubricant. The bearing in
Figure 10.34 is sealed on both sides; lubrication is
not required.
Replace the bearing in the slip ring end frame if its
grease supply is exhausted. No attempt should be
made to lubricate or reuse the bearing. To remove
the bearing from the slip ring end frame, press out
with a tube or collar that just fits inside the end
frame housing. Press from the outside of the
housing towards the inside.
To install a new bearing, place a flat plate over the
bearing and press in from the outside towards the
inside of the frame until the bearing is flush with the
outside of the end frame. Support the inside of the
END FRAME
BEARING
SLINGER
END FRAME
FLAT
RETAINER
COLLAR
COLLAR
SCREW
SHAFT
NUT
WASHER
FAN
PULLEY
COLLAR
ARMATURE SHAFT
MA1171
MA1181