Hudson 1955 Rambler, Technical & Service Manual

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1
OVERDRIVE SECTION
Overdrive—"Hornet", "Wasp" and "Rambler" Series
Overdrive—"Hornet", "Wasp" and "Rambler" Series
OPERATION
The overdrive unit, when in operation above the
governor cut-in speed, automatically reduces the
engine to rear axle ratio approximately 30%.
When overdrive operation is desired, the control
button is pushed to the forward position. The
car speed is then increased to a point higher
than the cut- in speed, which is determined by
the point setting of the overdrive governor.
As the governor points close, at approximately
30 miles per hour, the solenoid is energized.
This allows the locking pawl to engage the sun
gear hub and balk ring assembly when the accel-
erator is momentarily released. When the accel-
erator is again depressed the overdrive is in
operation. As this takes place, free wheeling
becomes inoperative, since free wheeling is
possible only below the cut-in speed determined
by the overdrive governor.
To lock out the overdrive the control button
must be pulled all the way out. This can be done
either when the car is in motion or when it is
parked. Locking out the overdrive while the car
is in motion can be done while the car is in the
free wheeling stage. The accelerator is de-
pressed so that the engine is driving the car,
and the control button is pulled out without
depressing the clutch. While still applying
pressure to the control button, the accelerator
should be momentarily released to complete the
shift.
An alternate method permits pulling the control
button back into conventional position during
the time the accelerator pedal is fully de-
pressed in the overtake position.
THE OVERDRIVE CONTROL UNITS
In order to service this control system, it is
very important to understand just how it works.
The follow. ing paragraphs explain the entire
overdrive control system.
The Electrical Circuits
The electrical system consists of the three
following circuits:
Governor Circuit—Light Line
Solenoid Circuit—Heavy Line
Kickdown Circuit—Dotted Line
"Hornet" and "Wasp" Series
The governor, solenoid, and kickdown circuits
can be traced as follows:
Governor Circuit
The governor circuit starts from the voltage
regulator armature terminal. It continues to
terminal No. "2" on the overdrive relay. The
current passes through the relay coil to
terminal No. "3". Then through the kickdown
switch to the "H" terminal on the governor and
open contacts "A" (Fig. 1).
Solenoid Circuit
The solenoid circuit starts from the "B"
terminal on