GMC 1976 ZEO 6083 Maintenance Manual page 403

ATTACHING NUTS
SI CHARGING SYSTEM
DIAGNOSTIC TESTER J-26290
NOTE :
For use on 120 volt negative ground
vehicles only . Perform test with lights and all
accessories off. After diagnosis has been made
and the problem corrected, use GO/No-Go Test
Light Indicator J-26290 again to verify proper
operation of charging system .
With the engine stopped, detach field and sensing
leads connector from the SI Delcotron and plug into
tester. Next plug the tester leads into the SI Delco
tron and attach tester ground clip to ground, as
shown in Figure 27 .
Engine Off
bridge .
Figure 26-Slip Ring End Frame
1 . If tester light flashes, go to engine fast idle .
2. If tester light remains on, the tester itself is
faulty .
3. If the tester light remains off, pull tester con-
nector plug from Delcotron.
a. If tester light flashes, replace rectifier
b. If tester light remains off, faulty tester or
no voltage to tester (broken or faulty connection).
ok .
ENGINE ELECTRICAL
6Y- 2 3
Figure 27-SI Delcotron Tester Tool J-26290
Engine at Fast Idle (1000 RPM or More)
4. If tester light remains off Delcotron system is
5. If tester light remains on, remove and check
the Delcotron.
6. If the tester light flashes, remove Delcotron
and check regulator, rotor field coil, brushes, and
slip rings .
GENERATOR REMOVAL
NOTE : Due to variations in design and equip-
ment, the replacement procedures will vary ac-
cordingly. The
removal and installation -
instructions following are intended only as a
guide. Additional operations will be required on
some vehicles to remove other equipment to per-
mit access to generator, belts, and/or brackets .
1 . Disconnect negative cables from batteries.
2 . Depress lock on connector and pull connector
out of socket on generator. Pull rubber boot off
"BAT" terminal and remove terminal nut. Discon
nect ground (GRD) terminal and remove wiring
clip .