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SI SERIES GENERATORS 6D1-3
As the generator speed and voltage increase, the voltage
between R2 and R3 increases to the point where the zener
diode D1 conducts.This turns on tran sistor TR2 which
causes TR3 and TR1 to turn off. With TR1 off, the field
current and system voltage decrease. D2 stops conducting
when the voltage drops to a certian level, causing TR3 and
TR1 to turn back on. This cycle repeats many tim es per
second to limit the generator voltage to a preset value.
Capacitor C1 sm oothes out the voltage across R3. Resis
tor R4 prevents excessive current through TR1 at high tem
peratures. Diode D2 prevents induced high voltages in the
field w indings when TR1 turns off. Resistor R2 is a therm is-
ter which causes the regulated voltage to vary with tem per
ature, thus providing the optim um voltage for charging the
battery.
Some installations do not use an indicator lamp. Instead
a resistor or resistance wire is used in its place. The charge
rate is then indicated by a voltm eter.
If an open should occur in the No. 2 term inal circuit, TR3
and TR1 will turn off, field current will stop and the indicator
lamp current will flow through R6 to ground, causing the
indicator lamp to come on. Also, an open in the field circuit
will cause the indicator lamp to turn on because indicator
lamp current will flow through R6 to ground.
If an open should occur in the No. 1 term inal circuit, the
indicator lamp will stay off, and the generator will not gener
ate current.
GENERATOR OUTPUT TEST
To check the generator in a test stand, proceed as fol
lows:
1. Make the connections as shown in figure 4, except
leave the carbon pile disconnected.
• The ground polarity of the battery and the gen
erator must be the same.
• Use a fully charged battery, and a 10 ohm resis
tor rated at six watts or more between the gener
ator No. 1 term inal and the battery.
2. Slowly increase the generator speed and observe the
voltage.
3. If th e v o lta g e is u n c o n tro lle d w ith sp e e d and
increases above 15.5 vo lts on a 12-volt system ,
replace the regulator and check the field winding.
4. If the voltage is below 15.5 volts on a 12-volt system,
connect the carbon pile as shown.
5. Operate the generator at m oderate speed as required
and adjust the carbon pile as required to obtain m axi
mum current output.
6. If the output is within 10 amperes of the rated output
as stamped on the generator frame, the generator is
good.
7. If the output is not within 10 am peres of the rated
output, keep the battery loaded with the carbon pile,
and ground the generator field (figure 5).
• The field ground tab is within 25 mm (1-inch) of
the casting surface. DO NOT force the screw
driver deeper into the end frame.
8. Operate the generator at a m oderate speed and
adjust the carbon pile as required to obtain m aximum
output.
9. If the output is within 10 amperes of the rated output,
replace the regulator and check the field winding.
1. "B A T ” T erm inal
2. No. 1 T erm inal
3. No. 2 T erm inal
5. G e n e ra to r
6. V o ltm e te r
9.
A m m e te r
B a tte ry
C arbo n Pile
F-04195
Figure 4 — Generator Bench Check
10. If the output is not within 10 am peres of the rated
output, check the field winding, diode trio, rectifier
bridge, and stator as described later under “ Inspec
tion and Repair” and “ Electrical T ests.”
DISASSEMBLY
SLIP RING END FRAME
❖
Disassemble (Figures 6, 7, 8, and 9)
Hold the generator in a vise, clam ping the m ount
flange lengthwise.
Make a scribe mark to help locate the fram e end parts
in the same position during assembly.
Four through bolts (27).
Slip ring housing (40) and stator (41).
Stator lead nuts.
Stator from the end frame.
Insulated screws (30) and ground screw (29) from the
brush holder (13).
Wire resistor (14).
Summary of Contents for 1989 Light Duty Truck
Page 1: ...vr V Light Duty Truck Unit Repair Manual...
Page 2: ......
Page 11: ...GENERAL INFORMATION OA 5 Figure 8 RV Models...
Page 13: ...GENERAL INFORMATION OA 7 Figure 11 ST Models...
Page 18: ......
Page 44: ......
Page 76: ...1B3 18 R 4 AIR CONDITIONING COMPRESSOR N...
Page 114: ......
Page 162: ......
Page 176: ...4B3 14 91 2 INCH RING GEAR...
Page 192: ...4B5 4 DANA REAR AXLES Figure 4 Spreading the Differential Case Figure 7 Removing the Ring Gear...
Page 218: ......
Page 220: ...4B6 2 12 INCH RING GEAR ROCKWELL F 04734 Figure 1 Rear Axle Components...
Page 229: ...12 INCH RING GEAR ROCKWELL 4B6 11 SPECIAL TOOLS Special Tools...
Page 230: ...4B6 12 12 INCH RING...
Page 240: ...4B7 10 LOCKING DIFFERENTIALS SPECIAL TOOLS Special Tools...
Page 260: ...4C2 6 93 4 INCH RING GEAR FRONT AXLE Figure 16 Removing the Pinion Inner Bearing...
Page 273: ...T TRUCK FRONT AXLE 4C3 3 F 05785 Figure 1 Axle Components...
Page 291: ...K TRUCK FRONT AXLE 4C4 3 Figure 1 Front Axle Com ponents K 15 25 Models...
Page 293: ...K TRUCK FRONT AXLE 4C4 5 Figure 3 Front Axle Com ponents K35 Models...
Page 318: ...C4 30 K TRUCK FBOHT AXLE...
Page 334: ......
Page 361: ...2 5 LITER L4 ENGINE 6A1 5 Figure 3 Cylinder Head Manifolds and Components...
Page 363: ...2 5 LITER L4 ENGINE 6A1 7 F 05715 Figure 5 Block and Components...
Page 395: ...2 8 LITER V 6 6A2 3 Figure 1 Engine Lubrication Diagram...
Page 396: ...6A2 4 2 8 LITER V 6 Figure 2 Engine Lubrication Diagram...
Page 424: ...6A2 32 2 8 LITER V 6...
Page 427: ...I 4 3 LITER V 6 6A3 3 Figure 1 Engine Lubrication Diagram B 07857...
Page 451: ...4 3 LITER V 6 6A3 27 SPECIFICATIONS ENGINE SPECIFICATIONS F 6344...
Page 457: ...4 8 LITER L6 6A4 3 Figure 2 Lubrication Diagram Front View...
Page 460: ...6A4 6 4 8 LITER L6 C 1 107 112 fK 108 3 109 165 129 B 05056 Figure 5 Block and Components...
Page 490: ...Ml...
Page 493: ...V8 ENGINE 6A5 3 Figure 1 Lubrication Diagram 5 0L and 5 7L Engines...
Page 494: ...6A5 4 V8 ENGINE Figure 2 Lubrication Diagram 5 0L and 5 7L Engines...
Page 530: ...6A5 40 V8 ENGINE Figure 81 Exhaust Manifold 7 4L Engines Figure 82 Water Pumps and Components...
Page 571: ...6 2 LITER DIESEL 6A7 35 Figure 58 Vacuum Pump Installed...
Page 576: ......
Page 582: ...6C1 6 MODEL 1MEF CARBURETOR Figure 9 Monojet Model 1MEF...
Page 604: ...6C2 6 MODEL M4MEF CARBURETOR Figure 9 Model M4MEF...
Page 640: ...6C4 8 MODEL 700 THROTTLE BODY...
Page 652: ...nmm...
Page 672: ......
Page 693: ...DISTRIBUTORS 6D5 13 Figure 27 Testing the Pickup Coil Figure 28 Testing the Ignition Coil...
Page 696: ......
Page 698: ...7A1 2 700 R4 AUTOMATIC TRANSMISSION Figure 1 Case and External Parts J H 0 0 5 3 7 0 0 R 4 R 2...
Page 745: ...700 R4 AUTOMATIC TRANSMISSION 7A1 49...
Page 762: ...7A2 2 400 475 AUTOMATIC TRANSMISSION Figure 1 Case and External Parts H H 0021 400 R 3...
Page 773: ...400 475 AUTOMATIC TRANSMISSION 7A2 13 Figure 29 Internal Parts H H 0 0 4 3 4 0 0 R 2...
Page 797: ...400 475 AUTOMATIC TRANSMISSION 7A2 37 Figure 93 Control Valve Assem bly...
Page 803: ...400 475 AUTOMATIC TRANSMISSION 7A2 43 Figure 104 Bushing Replacement Procedure...
Page 808: ...J c I i sal...
Page 838: ......
Page 840: ......
Page 842: ......
Page 850: ...7B1 12 HM 290 MANUAL TRANSMISSION J i t i a x V L...
Page 856: ...7B1 18 HM 290 MANUAL TRANSMISSION...
Page 892: ...7B1 54 HM 290 MANUAL TRANSMISSION Figure 93 Special Tools...
Page 897: ...HM 117 TRANSMISSION 7B2 5...
Page 901: ...HM 117 TRANSMISSION 7B2 9 B 05180 Figure 17 Installing the 1st and 2nd Synchronizer...
Page 912: ...20 HM...
Page 924: ...7B3 12 NEW PROCESS TRANSMISSION SPECIAL TOOLS...
Page 927: ...BORG WARNER TRANSMISSIONS 7B4 3 Figure 2 77 mm Transmission and Components...
Page 940: ...i ii iii m i in m i...
Page 944: ...7D1 4 TRANSFER CASE FO 5688 Figure 3 NP205 Transfer Case...
Page 952: ...7D1 12 TRANSFER CASE...
Page 963: ...NEW PROCESS 241 TRANSFER CASE 7D2 11 Figure 17 Oil Pump Pickup Screen Doweled Case Holes...
Page 964: ...7D2 12 NEW PROCESS 241 TRANSFER CASE Figure 18 NP 241 Transfer Case Cut Away...
Page 978: ......
Page 981: ...BORG WARNER 1370 TRANSFER CASE 7D4 3 J...
Page 992: ...7D4 14 BORG WARNER 1370 TRANSFER CASE Figure 26 Installing the Rear Output Yoke...
Page 993: ...BORG WARNER 1370 TRANSFER CASE 7D4 15 Figure 27 BW 1370 Transfer Case...
Page 997: ......
Page 998: ...X 8937...