Ford Corsar Repair Manual page 837

CHARGING SYSTEM -Alternator-
l
CA2OE
l
6. Unsolder the 3 stator connections
from rectifier assembly and remove
stator.
7. Remove screws @ and terminal
nuts (B*). Withdraw rectifier assembly.
8. Hold rotor @ in vice (soft
jaws!) and unscrew pulley retaining nut
0.
9. Remove pulley @ fan Q
and
2 spacers.
10. Drive end plate can now be sup-
ported on a press and the rotor
@
pressed out.
11. Remove ball bearing in drive end
plate by unscrewing two screws @ and
remove ball bearing
@.
12. Remove ball bearing @ on slip
ring end of rotor with a suitable puller.
C L E A N I N G
Thoroughly clean all parts with
compressed air, d o not immerse wind-
ings and bearings in solvents. The free
passage of cooling air around the heat
Take special care of
solder connections
sinks is essential for maximum ef-
ficlency, therefore dirt and oil traces
must be cleaned from and around the
rectif~er assembly.
TEST1
NG
I N D I V I D U A L P A R T S
Rectifier assembly
The rectifier assembly is not repair-
able and should, in case of diode
failure, be replaced. In order to estab-
lish whether the diodes are functioning
properly observe the following points:
Use only test lamps up to 24V.
With diodes of normal
(t)
polarity the
test lamp must light up if the positive
probe of the test lamp is connected to
the anode and the negative probe to
the cathode (housing). This process
has to be reversed for negative diodes.
(See Figure 1 .)
There are two main possibilities
w h c h can destroy a diode during
service, either breakdown in resistance
to current flow caused by h g h current
and high temperature, or open circuit
in both directions. This is almost
always the consequence of excess volt-
age.
these
Negative heat sink
Positwe heat s ~ n k
X 0 9 4
Fig 3 Rectifier connections
Power diodes
test probes (polarity) whether the
diodes are functioning properly. If
Apply test probes as described above diodes
C-B, F-C
or E-D are short
to points B, C, D o r E, F , G (see Figure
circuited. all 6 power diodes will show
3) a n d t h e a p p r o p r i a t e h e a t s i n k . a short clrcult when tested with the
E s t a b l i s h b y r e v e r s i n g t h e testlamp.
E x c i t e r d i o d e s
Apply test probes between points
A
and B , C , I). By reversing to probes it
can
be established
~f one or several of
the exclter diodes failed due to an
open or short circuit.
S t a t o r winding
Test stator for short circuit to
ground with a test lamp of up to 40V.
Test winding resistance between
phases according to the values given.
Refer to Service Data and Specifica-
tions. Insulation and short circuit tests
on windings should only be carried out
with the diodes disconnected.
T e s t i n g of exciter winding
Test for short circuit to ground
with a test lamp of up t o 40V.
Measure the resistance of the exciter
winding between the slip rings. Resist-
ance should be according to the values
gven. Refer to Service Data and Speci-
fications.
Regulator and brush
assembly
The regulator is not serviceable and
should be replaced as an assembly.
If the brushes are worn, new
brushes should be soldered into the
brush holder allowing 0 . 4 3 to 0.47"
( l l to 12 mm) of brush to protrude
from holder. Worn slip rlngs can be
turned in a lathe In the usual manner.
Ball bearings
Check ball bearings for wear and
roughness. Renew defective bearings
with approved bearings only hnd lubri-
cate wlth BOSCH Grease Etlv34.
ASSEMBLY
(Reverse disassembly procedure)
a)
Tlghten the through bolts evenly.
The air gap between rotor and stator
must be equal at all polnts If the alr
gap
I S
not even, loosen the through
bolts and reposltlon the end plates on
the stator
b) T ~ g h t e n pulley nut to 40 to 50
ft-lb (S S3 to 6 9 1 kg-m) torque