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DIAGNOSIS
STARTER MOTOR TESTS
Before disassembling the starter motor for repair, the
following test should be made.
N O T I C E : N e v e r o p e r a t e t h e s t a r t e r m o t o r
m o r e t h a n 3 0 s e c o n d s a t a t i m e w i t h o u t
p a u s i n g to a l l o w i t to c o o l f o r a t l e a s t tw o
m in u t e s . O v e r h e a t in g , c a u s e d b y t o o m u c h
c r a n k in g , w ill d a m a g e t h e s t a r t e r m o t o r .
NO-LOAD TEST
Connect a voltmeter from the motor terminal to the
motor frame and an RPM indicator to measure arma
ture speed (figure 2). Connect the motor and an amme
ter in series with a fully charged battery of the specified
voltage, and a switch in the open position to the switch
terminal. Close the switch and compare the RPM, cur
rent, and voltage readings with the specifications at the
end of this section. It is not necessary to obtain the
exact voltage specified as a good reading can be made
by understanding that if the voltage is slightly higher the
rpm will be slightly higher, with the current remaining
basically unchanged. However, if the exact voltage is
desired, a carbon pile connected across the battery can
be used to reduce the voltage to the specified value.
Compare the test results as follows:
1. Rated current draw and no-load speed indicates
normal condition of the starter motor.
2. Low free speed and high current draw indicates:
• Too much friction.
Tight, dirty or worn bear
ings, bent armature shaft or loose pole shoes
allowing the armature to drag.
• Shorted armature.
This can be further checked
on a growler after disassembly.
• Grounded armature or fields.
Check further
after disassembly.
3. Failure to operate with high current draw indicates:
• A direct ground
in the terminal or fields.
•
Seized bearings.
This should have been noted
by turning the armature by hand.
4. Failure to operate with no current draw indicates:
•
Open field circuit.
This can be checked after
disassembly by inspecting internal connections
and tracing the circuit with a test lamp.
•
Open armature coils.
Inspect the commutator
for badly burned bars after disassembly.
• Broken brush springs, worn brushes.
High
insulation between the commutator bars or oth
er causes which would prevent good contact
between the brushes and commutator.
5. Low no-load speed and low current draw indicates
a higher internal resistance due to poor connec
tions, defective leads, dirty commutator and causes
listed under step 4.
6. High free speed and high current draw indicates
shorted fields. If shorted fields are suspected,
replace the field coil assem bly and check for
improved performance.
BATTERY
CARBON
PILE
R.P.M.
INDICATOR
AMMETER
VOLTMETER
A
L,
batj
J
e
lsfc
I
MJijg
4
CRANKING
MOTOR
3
2 9 0 6 r4 6 9 2
Summary of Contents for S Series 1994
Page 1: ......
Page 11: ...VIEW A p n n n j VIEW C F7554 Figure 10 Hydra Matic 4L60 E Transmission I D Location...
Page 24: ...NOTES...
Page 26: ......
Page 69: ...NOTES...
Page 71: ...3 2 STEERING...
Page 73: ......
Page 84: ......
Page 102: ...40...
Page 130: ...NOTES...
Page 146: ...NOTES...
Page 162: ...NOTES...
Page 166: ...Figure 5 Removing the Pinion Flange Figure 6 Pressing the Drive Pinion from the Cage...
Page 178: ...Figure 3 Spreading the Differential Case Figure 4 Removing the Differential...
Page 190: ...NOTES...
Page 202: ...NOTES...
Page 206: ...F5785...
Page 212: ...B Button Moved Out of Bearing Bore F5791...
Page 228: ...NOTES...
Page 232: ......
Page 234: ......
Page 236: ...Adjuster 63 Bolt 64 Lock Figure 10 Turning the Adjuster Plug K3 Models...
Page 237: ...Figure 13 Removing the Pinion Seal 39 Bearing Cup Figure 16 Removing the Inner Bearing Cap...
Page 261: ...F7475...
Page 267: ...B Button Moved Out of Bearing Bore F5791...
Page 294: ...NOTES...
Page 300: ...NOTES...
Page 318: ...NOTES...
Page 322: ...SR207LN2 EDS...
Page 324: ......
Page 326: ...OVERHEAD OILING AND RETURN MAIN OIL GALLERY N30005 6A2 J EDS...
Page 368: ...103 153 127 V1200...
Page 370: ......
Page 372: ......
Page 374: ...F9375 Figure 7 Engine Lubrication Diagram Engines Without Balance Shaft...
Page 376: ...Figure 9 Engine Lubrication Diagram Engines With Balance Shaft...
Page 399: ...V2974...
Page 410: ......
Page 412: ...195 196 201 174 252 163 165 164 244 3706r3924...
Page 452: ......
Page 454: ...163 164 V1202...
Page 456: ...20 21x 302 210 4 0 41 2 5 2 5 1 2 51 4 2 e3 54 3 9 252 252 S 255 255 25 6 256 209 V1196...
Page 458: ...100 1 8 4 185 183 177 v 75 201 3706r1204...
Page 460: ......
Page 510: ......
Page 512: ...V2131...
Page 514: ...110 106 106 103 90 93 89 88 87 86 v 7 7 7 7 j A _ 111 f t 2 a a s 53 49 L 47 46 3706r4751...
Page 516: ...259 260 150 237 S lM 180 167180 J 1 82 183 170 169 1 1 78 1 7 9 213212 2 0 7 205 r i 3706r4752...
Page 566: ...NOTES...
Page 574: ...NOTES...
Page 618: ...SPECIAL TOOLS...
Page 620: ...NOTES...
Page 672: ......
Page 682: ......
Page 686: ......
Page 694: ...RH0213 4L60 E...
Page 695: ...657 659 m i J 8092 H J 34196 4 3 34196 5 657 658 665 J 23907 J 7004 1 J 8092 RH0214 4L60 E...
Page 696: ...J 8092 J 34196 4 33 31 J 8092 RH0215 4L60 E...
Page 697: ...SPECIAL TOOLS...
Page 698: ...SPECIAL TOOLS...
Page 758: ...RH0194 4L80 E...
Page 764: ......
Page 770: ...SPECIAL TOOLS...
Page 771: ...SPECIAL TOOLS CONT...
Page 772: ......
Page 775: ......
Page 776: ......
Page 785: ......
Page 804: ...NOTES...
Page 806: ......
Page 808: ......
Page 822: ...3707r5079...
Page 840: ......
Page 848: ...NOTES...
Page 852: ......
Page 860: ...F5435...
Page 866: ......
Page 878: ...F9167...
Page 882: ...16 FrontOutputShaft 18 DrivtQNr 19 DrivenGm t 20 DriveChain 22 FrontOutputBearing V2836...
Page 890: ...F9168...
Page 908: ......
Page 919: ......