Off-Vehicle Testing; Starter Motor Full-Lad Current Test - Jeep J-10 Series 1982 Technical & Service Manual

1F-18 STARTING SYSTEMS
(2) Disconnect and ground ignition coil secondary
wire.
(3) Connect remote control starting switch between
battery positive terminal and S-terminal on starter
solenoid.
NOTE: Do not consider the initial voltage at the begin
ning of engine cranking. A very hot or very coldengine
may cause a current ofUOO to 600 amperesfor thefirst
few revolutums. Note the voltage after thestarter motor
has obtainedits maximum rpm.
CAUTION: Do not operatefor more than 15 seconds.
(4) Connect battery-alternator-starter motor tester
leads as depicted in figure 1F-14. Operate remote control
starting switch and note voltage indicated on voltmeter
while starter motor is rotating engine.
(5) Release remote control starting switch.
(6) Turn load control knob toward INCREASE
(clockwise) until voltmeter indication matches that ob
tained when starter motor was rotating engine.
o o o o o o
SOLENOID
STARTER
MOTOR
BATTERY-
ALTERNATOR-
REGULATOR-
STARTER MOTOR
TESTER
I'
^\ AJ42176
Fig. 1F-14 Starter Motor Full-Lad Current Test
(7) Switch to AMP position and note current in
dicated on ammeter scale. This is current being used by
starter motor under full-load conditions. If current is
not within 150 to 180 amperes for six-cylinder engines or
160 to 210 amperes for eight-cylinder engines at room
temperature, remove starter motor from engine for
bench testing.
Neutral Safety Switch Test
Remove wire connector from switch and test for conti
nuity between center terminal pin and transmission
case. Continuity should exist only when automatic
transmission is in Park or Neutral position.
NOTE: Probe-type tips are required on ohmmeter test
leads. Ifnot available, push cotter pins into switch con
nector to provide contactsfor aligator jaw-type test lead
terminals.
NOTE: Check linkage adjustment before replacing
switch.
OFF-VEHICLE TESTING
No-Load Test
The starter motor no-load test results will indicate
faults such as open or shorted windings, worn bushings
(rubbing armature) or bent armature shaft.
NOTE: The tester load control knob must be in the
DECREASE(extremecounterclockwise) position.
(1) Operate starter motor with test equipment con
nected as diagramed in figure 1F-15. Note voltage
indication.
(2) Determine exact starter motor rpm using me
chanical tachometer (not shown).
NOTE: To use a mechanical tachometer, remove the
sealfrom the end of the drive end housingand clean the
grease from the end of the armature shaft.
(3) Disconnect starter motor from battery.
(4) Turn load control knob toward INCREASE
(clockwise) until voltage indication matches that ob
tained with starter motor connected to battery.
(5) Switch to AMP position and note current. If less
than specification, starter motor has high electrical re
sistance and should be repaired or replaced. If current is
more than specification and starter motor rpm is less
than specification, disassemble, clean, inspect and test
starter motor as outlined in following paragraphs.