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14-12
Inspect contact bolts and contact
plate for wear and replace worn con-
tacts.
The short contact bolt is re-
tained in place, after the terminal
nut is removed, by an external con-
necting strap from the solenoid wind-
ing terminaL This connecting strap
can be removed by prising the strap
away from the switch cover with a
screw
driver.
A replacement bolt can
be lightly pressed into the connecting
strap and after two or more threads
have entered, the terminal nut can be
used to draw the bolt into
place.
The moving contact is secured by
a contracted
washer.
This washer can
be removed with a pair of side-cut-
ters. After fitting a new moving con-
tact, a circlip and cup washer must be
used to secure the contact; crimp cup
washer over circlip.
The operation of the detached
switch can be checked by connecting
a battery supply through a variable
resistance to both pull-in and hold-
in windings and increasing the volt-
age gradually until at 6.0 volts or less
the plunger moves into its operational
position.
The plunger should return
to the rest position when the voltage
is reduced to, from 0.05-0.4 volts.
When an ignition coil resistor short
circuiting terminal No. 16 or C is
incorporated in the switch cover, the
terminal must be energised when the
switch is in the closed position.
A~SEMBLY
L
Replace drive assembly (16).
2.
Fit the stop ring (18) on the
armature shaft to allow the spring
ring ( 19) to fit in its groove in the
armature shaft.
3.
Slide the stop ring (18) over
the spring ring ( 19) to lock the spring
ring in position.
4.
Assemble the armature (15)
and engaging lever (11) in the drive
end housing (17) and replace the
engaging lever fulcrum bolt.
5.
Insert the armature and drive
end housing assembly in to the car-
cass.
6. 'Replace the brush holder plate
(7) 'ind the brushes (6).
7.
Assemble the commutator end
cover and through
bolts.
8.
Replace the circlip (3) the
bearing cap (2) and the bearing cap
screen (2).
9.
Refit the solenoid and attach-
ing
screws.
10.
Reconnect the solenoid switch
to starter motor
lead,
to the solenoid
GROUP 14- STARTING SYSTEM
terminal (9).
IMPORTANT:
Ensure
that a
water tight seal is made at rubber
packing
(13).
MECHANICAL ADJUSTMENTS
Armature End Play
The armature end play is the
lengthwise travel (longitudinal) of
the armature in its bearings. Too
little or too much end play results in
increased wear of the bearings.
The end play is adjusted by plac-
ing or removing shims at the com-
mutator end between the end cover
and circlip on the armature. Adjust
to
specification.
Armature Braking Torque
The total armature braking torque
is composed of brush, bearing and the
auxiliary armature brake torque.
Too high a braking torque results
in excessive mechanical wear and
armature brake heating.
Too low a braking torque results in
extended starter stopping
time.
Also,
the starter overrunning acceleration
will be too high. Armature torque can
be measured with a torque
balance.
Clutch Overrunning Torque
The overrunning torque of the
clutch assembly is the force necessary
to turn the pinion in a rotary direc-
tion while the armature shaft is held
s€ationary. Too low an overrunning
torque may prevent starter power
application.
If
the overrunning torque
is too high, the armature can reach
too high e speed and may be dam-
aged.
For measuring overrunning torque,
move the pinion forward at least 0.4",
with armature stationary measure
torque in direction of rotation. Clutch
assemblies not conforming to the
specifications must be replaced.
1-------11•
ELECTRICAL TESTS OF
ASSEMBLED STARTER MOTOR
The electrical test values depend
upon the condition of the battery
(capacity and charge). The testing
period also plays an important part
(heating of the starter and battery
discharge)
.
Long cables on the test
bench also influence starter
perform-
ance.
The test period should therefore
be as short as
possible.
The batteries
must be in good condition and well
charged or the electrical values of a
faulty starter will differ considerably
from the specified test
data.
1. Circuit Diagram
The internal circuitry of the starter
and the electrical connections are
given in the diagram above.
2. Short-circuit Test
Clamp starter in test bench and
connect in accordance with the wiring
diagram.
The ring gear of the test bench and
the starter pinion must have the same
pitch; adjust backlash and out of
mesh
clearance.
Operate starter and apply
·
test
bench brake until pinion is almost to
a
standstill.
At this moment read cur-
rent and voltage which must conform
to
specifications.
3. Load Test
Clamp starter and connect as in
short circuit test. Operate starter and
apply brake until the specified cur-
rent draw is recorded, read voltage
and
RPM.
4.
Free Running Test
Re-position starter on test bench so
that pinion and ring gear cannot
engage.
Connect as for previous
tests.
Operate starter, read amperage,
volt-
age and
RPM.
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