Hudson 1955 Rambler, Technical & Service Manual

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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
The screwshaft on the FOLO-THRU Drive is
divided into two sections with a dentil
connection between them. Therefore, when the
engine is driving the pinion at a greater speed
than the driving effort of the starting motor,
the pinion and barrel assembly, control nut, and
screwshaft over-run the starting motor armature
shaft. This over-running serves as a safety
factor preventing damage to the starting motor.
When the engine does not continue to run and
slows down, the speed of the pinion and barrel
assembly, control nut, and screwshaft also
decreases. Cranking is automatically resumed
immediately after the speed of the over-running
parts reaches that of the starting motor
armature shaft provided the starter switch has
been kept closed.
Intermittent action between over-running and
cranking occurs until the engine is firing so
that its speed reaches the predetermined rate
at which the detent pin is centrifugally forced
against the detent spring, thereby compressing
it. The detent pin thus becomes disengaged from
the screwshaft notch which permits the drive
pinion to automatically demesh from the fly-
wheel ring gear.
Drifting of the pinion and barrel assembly
towards the flywheel ring gear while the engine
is running is prevented by a spring loaded
anti-drift pin which engages a slope on the
screwshaft. This anti-drift pin, also assembled
in the control nut, is identical in design to
the detent pin. However, due to the difference
in function, the spring tension is not the same.
In general, the anti-drift spring is stronger
than the detent spring.
The Bendix Folo-Thru Drive should be cleaned
and oiled with a penetrating oil, as any
accumulation of dirt on the drive might restrict
the free movement of the pinion.
IGNITION SYSTEMS
The ignition system consists of the ignition
coil, condenser, distributor, high tension
wiring, spark plugs, ignition switch, and a
source of electrical energy — the battery or
generator. There are two circuits in the
ignition system. The primary circuit includes
the source of electrical energy, the distribu-
tor contact points, the condenser, and the
primary winding of the ignition coil. The
secondary circuit includes the secondary wind-
ing of the ignition coil, the rotor, distributor
cap, the high tension wiring, and spark plugs.
The primary circuit is completed and broken
by the circuit breaker mechanism of the distrib-
utor, causing a build-up and collapse of a
magnetic field in the ignition coil. The
condenser is connected across the distributor
contact points. When the points open, the
current tries to continue flowing.
Without the condenser, the current would form
an arc across the separating points. The
condenser prevents this because it has the
ability or capacity to store up electrical
energy. The current instead of forming an arc,
flows into the condenser. Therefore, the
condenser brings the current flow to a quick
stop. This causes the magnetic field in the
coil, sustained by the current flow, to
collapse quickly. It is this quick collapse of
the magnetic field which induces the high
voltage in the secondary coil windings. The
high voltage is distributed to the correct
cylinder spark plug wire by means of the rotor
and distributor cap.
DISTRIBUTORS (AUTO-LITE)
"Hornet" V-8 Series
A dual contact distributor is used on the V-8
series engine for required increased secondary
ignition efficiency.
The increased efficiency is a result of
better magnetic induction on the secondary
coil, through longer operation of the primary
coil. This is accomplished by increasing the
duration of current flow through the primary
coil, between the firing points of the distrib-
utor, with dual contacts connected in parallel
and staggered around the eight lobe cam.
Connected in parallel and staggered around the
cam, one set of contacts is actuated later than
the other, so the two contact points are in a
state of closing and opening. The circuit
closing contact is moving toward its closed
position, while the circuit opening contact is
moving toward its open position. For a brief
period, both contacts are then open, opening
the primary circuit and causing a spark plug
to fire. With this arrangement, the dwell angle
is increased considerably, permitting the
available voltage from the secondary circuit
to be more fully utilized. The dwell angle is
the angle of cam rotation through which the
primary circuit remains closed. The coil
primary offers inductive reactance to a
current flow, so some time is required to build
the current flow up to its full value in the
primary. The dual contacts more adequately
provide for this required time.
The distributor is fully automatic with both
governor and vacuum control of the timing. The
diaphragm is linked to a pin on the upper plate
which carries the contacts. This plate is
pivoted at one side and rides on flat,
absorbent bronze bearings. The timing is
changed by the plate movement. The maximum
vacuum advance is limited by a stop which is
a part of the vacuum chamber linkage.
"Hornet" 6 and "Wasp" Series
The "Hornet" 6 (Model IAT-4203-A) and "Wasp"
Series (Model IAT-4202) Auto-Lite Distributors
are fully automatic with both governor and
vacuum control of the timing. The diaphragm is
linked to a pin on the upper plate which
carries the contacts. This plate is pivoted at
one side and rides on flat absorbent bronze
bearings.
The timing is changed by the plate movement.
The maximum vacuum advance is limited by a stop
which is a part of the vacuum chamber linkage.