Hudson 1955 Rambler, Техническое и сервисное руководство

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Overhaul Procedure
At periodic intervals, the starting motor
circuit should he thoroughly checked and the
motor removed from the engine for cleaning and
checking.
Disassembly
When disassembling the motor, each part should
be removed and cleaned and inspected for wear
or damage. The drive should be cleaned and
inspected for wear. Bearings should be checked
for proper clearance and fit. All insulation
should be free from oil and in good condition.
The armature, field coils and brushes should
be checked for grounds or open circuits.
Brushes
The brushes should slide freely in their
holders and make full contact on the commuta-
tor. Worn brushes should be replaced.
Brushes that are soldered to the field coil
lead should be unsoldered and have the loop
in the field coil lead opened. The new brush
pigtail should be inserted to its full depth
in the loop and then clinched before re-
soldering. A good soldering must be done to
insure no loss of starting motor efficiency
due to a poor contact.
Brush spring tension should be checked with a
spring scale. To check the tension of reaction
type brush springs, hook the scale under the
brush spring near the brush and pull on a line
parallel with the side of the brush. Take the
reading just as the spring leaves the brush.
If the brush spring tension is too low, there
will be a loss of efficiency due to poor brush
contact. If the tension is too great, the
commutator and brushes will wear excessively
and have short life. It is, therefore,
important that the brush spring tension be
kept within 42 to 53 ounces. To change the
spring tension twist the spring at the holder
with long nosed pliers.
Armature
Check the commutator for wear or discolor-
ation. If the commutator is only slightly
dirty or discolored, it can be cleaned with
Nos. 00 and 000 sandpaper. Blow the sand out
of the motor after cleaning the commutator.
If the commutator is rough or worn, the
armature should be removed and the commutator
turned down in a lathe.
The armature should be visually inspected for
mechanical defects before being checked for
shorted or grounded coils. For testing arma-
ture circuits, it is advisable to use a set
of test probes.
To test the armature for grounds, touch one
point to a commutator segment, and - touch the
core or shaft with the other probe. Do not
touch the points to the bearing surface or to
the brush surface as the arc formed will burn
the smooth finish. If the lamp lights, the
coil connected to the commutator segment is
grounded.
To test for shorted armature coils, a growler
is necessary. The armature is placed against
the core and a steel strip held on the armature.
The armature is then rotated slowly by hand. If
a shorted coil is present, the steel strip will
become magnetized and vibrate.
Field Coils
Using test probes, check the field coils for
grounds. To test for grounds, place one probe
on the motor frame or pole piece and touch the
other probe to the field coil terminals. If a
ground is present, the lamp will light.
Inspect all connections to make sure they are
proper. ly clinched and soldered. Inspect the
insulation for evidence of damage.
Brush Holder Inspection
Using test probes, touch each insulated brush
holder with one probe and a convenient ground
on the commutator end head with the other probe.
If the lamp lights, it indicates a grounded
brush holder.
Pinion Housing
Inspect housing for cracks and bearing for wear.
Assembly
When assembling absorbent bronze bearings,
always use the proper size arbor as these arbors
are designed to give the proper bearing fit.
Soak the bearing in oil before assembling in
the bearing bore.
The pinion end of the armature shaft should be
given a light wipe with very light oil when
assembling.
Brushes should be correctly installed and
connected as previously outlined in order to be
sure of proper starting motor efficiency.
Proper brush seating should be insured by
sanding the brush to fit the commutator. To sand
the brush, wrap a strip of No. 00 sandpaper
around the commutator and turn the armature
slowly in the direction of rotation. Blow the
sand out of the motor after sanding.
Lubrication
When the starting motor is overhauled, the
bearings should be soaked in oil and the bearing
seats should be given a light wipe of oil.
Bench Test
The motor should first be checked to see that
the free running voltage and current are within
specifications. To test, connect the motor to
a battery, ammeter and voltmeter. If the current
is too high, check the bearing alignment and
end play to make sure there is no binding or
interference.
Using a spring scale and torque arm, check the
stall torque to see that the motor is producing
its rated cranking power. The stall torque will
be the product of the spring scale reading and
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T E C H N I C A L S E R V I C E M A N U A L