Starter Motor Test; No-Load Test; Starter Motor Shimming And Mounting - Jeep J-10 Series 1982 Technical & Service Manual

(2) Wiring: Inspect wiring for damage. Inspect all
connections at starter motor solenoid, relay (if equip
ped), neutral safety switch (if equipped), ignition/start
switch, and battery, including all ground connections.
Clean and tighten all connections as required.
(3) Solenoid and Ignition/Start Switch: Inspect
solenoid and switch to determine their condition. Also, if
equipped with automatic transmission, inspect condi
tion of starter motor relay.
(4) Starter Motor Noise: To correct starter motor
noise during starting, use the following procedure:
(a) Refer to Starter Motor Noise Diagnosis
Chart to determine problem.
(b) If complaint is similar to first two condi
tions, correction can be achieved by proper "shimming"
as follows.
1. Remove flywheel or drive plate ring gear
inspection plate.
2. Inspect flywheel or drive plate and ring
gear for damage; i.e., warp, unusual wear and excessive
runout. Replace flywheel, ring gear or drive plate as
necessary.
3. Disconnect battery negative cable (to
prevent inadvertant cranking of engine).
NOTE: Two shim thicknesses are available. One is
0.015 inch (0.381 mm) and the other 0.01*5 inch (1.11*3
mm). If shims are not available, they can be fabricated
from plain washers or other suitable material.
4. If complaint is similar to first condition,
starter motor must be moved toward flywheel/drive
plate. This can be accomplished by shimming (fig. 1F-3)
only outboard starter motor mounting pad. (This is gen
erally condition that causes broken flywheel ring gear
teeth or starter motor housings).
5. If complaint is similar to second condi
tion, starter motor must be moved away from fly
wheel/drive plate. This is accomplished by installing
shim(s) (fig. 1F-3). More than one shim may be required.
(c) Conditions 3 and 4 may require starter
motor replacement or repair in some instances.
(5) Starter Motor: If battery, wiring, switches, so
lenoid and relay (if equipped) are in satisfactory condi
tion, and engine is known to be functioning properly,
remove starter motor and follow test procedures out
lined below.
CAUTION: Never operate the starter motor more than
for a 30-second duration without pausing to allow it to
cool for at least two minutes. Overheating, caused by
excessive cranking, will seriously damage the starter
motor.
Starter Motor Test
A general diagnosis is described at the end of this
section. Once a problem has been traced to the starter
motor, proceed to the test procedure outlined below.
STARTING SYSTEMS 1F-3
rHrngrre 11 d i — r a m — — — i m . -
SHIMS
FRONT
90557
Fii. 1F-3 Slarisr itfalcr Shimming and Mounting
7&i Frscudura
With the =ur?i.«r motor removed from the engine, the
pinion gear should be tested for freedom of operation by
turning it on the screw shaft. The armature should be
tested for freedom of rotation by prying the pinion gear
with a screwdriver to engage it with the shaft. Tight
bearings, a bent armature shaft, or a bent frame will
cause the armature to not rotate freely. If the armature
does not rotate freely, the motor should be disassembled
immediately. However, if the armature does rotate
freely, the motor should be given a no-load test before
disassembly.
l\'J Lo.J lul
Connect a voltmeter iiig. lF-4) between the motor
terminal and the motor frame, and use a tachometer to
measure armature speed. Connect the motor and an
ammeter in series with a fully charged battery of the
specified voltage, and a switch (in the open position)
from the solenoid battery terminal to the solenoid
switch terminal. Close the switch and compare the rpm,
current, and voltage with those listed in the specifica
tions. It is not necessary to obtain the exact voltage
specified because an accurate interpretation can be
made by recognizing that if the voltage is slightly
higher, the rpm will be proportionately higher, with the
current remaining the same. However, if the exact volt
age is desired, a carbun pile rheostat connected across
the battery can be used to reduce the voltage to the
specified value. The specified current flow includes the
solenoid current flow. Make disconnections only with
the switch open, interpret the test results as follows:
(1) Rated current flow and specified no-load speed
indicate normal condition of starter motor.