Rectifier Bridge-C.s.i. Generator - Pontiac Grand Prix Service Manual

6E-10
1969 PONTIAC SERVICE MANUAL
SINGLE CONNECTOR
OHMMETER
THREE CONNECTORS
Fig. 6E-17 Checking Diode Trio
-
C.S.I. Generator
To remove diode trio, proceed as follows:
1. Remove three stator attaching nuts.
2. Remove stator.
3. Remove diode trio lead clip attaching screw and
remove diode trio. Note that the insulating washer on
the screw is assembled over the top of the diode trio
connector.
OHMMETER
Fig. 6E-18 Checking Rectifier Bridge Diodes-C.S.I.
Generator
NOTE: i'bo diode trios differing in appearance are used
in the 1969 C.S.I. generator. Either one of these diode
trios may be used in any C.S.I. generator, as (he two are
completely interchangeable.
To check the diode trio, after removing it from the end
frame assembly, .connect an ohmeter having a 1 1 /2
volt cell, and using the lowest range scale, to the single
brush connector and one of the stator lead connectors
(Fig. 6E-17). Observe the reading. Then reverse the
leads to the same two connectors. Repeat this test with
each of the other two stator lead connectors. If any or
all give readings when reversing connections which are
the same, replace the diode trio. A good diode trio will
give one high and one low reading.
CAUTION: Do not use high voltage, such as a I10 volt
test lamp, to check this unit.
RECTIFIER BRIDGE-C.S.I. GENERATOR
The rectifier bridge of the C.S.I. generator contains all
of the diodes found in the heat sink and slip ring end
frame of the standard generator. If one diode is
defective, the entire rectifier bridge must be replaced.
To check the rectifier bridge, connect an ohmeter to
the ground heat sink and base of m e of the three
terminals (Fig. 6E-18). Then reverse the connections to
the grounded heat sink and base of the same terminal.
If both readings are the same, replace the rectifier
bridge. A good rectifier bridge will give one high and
one low reading.
Repeat this same procedure between the grounded
heat sink and the other two terminals, and between
the insulated heat sink and each of the three terminals.
If at least one pair of readings is the same, the
rectifier bridge must be replaced.
CA UTION: Do not use high voltage, such as a 110 volt
test lamp, to check this unit. NOTE: Two rectifier
bridges, ddiffering in appearance are used in the 1969
C.S.I. generator. Either one of these rectifier bridges
may be used in any C.S.I. generator, as the two are
completely interchangeable.
To replace the rectifier bridge, proceed as follows:
I . Remove the attaching screw and the "BAT"
terminal screw.
2. Disconnect the capacitor lead.
3. Remove rectifier bridge. Note the insulator between
the insulated heat sink and end frame (Fig. 6E-18).
BRUSHES
-
STANDARD GENERATOR
BRUSHES AND/OR VOLTAGE REGULATOR
-
C.S.I. GENERATOR
1. Remove two brush holder screws and stator lead to
strap attaching nut and washer (Fig. 6E-13 or 6E-14).