Service Manual – SC8000
eel S ste
raction
unctional escri tion
vervie
The traction wheel system includes the hydraulic traction drive motor and drive wheel, and the foot pedal/
hydroback system.
The traction drive motor is driven
by the variable-displacement
Piston Pump
which allows speed
and directional control. The
Piston
Pump
and traction drive motor
hydraulic system is a closed
system, but allows for programmed
oil leakage through the
Piston
Pump
for lubrication and cooling
purposes. This leaked oil returns
to the reservoir and requires
make-up oil that is supplied to the
Piston Pump
through the charge
circuit.
iston u
The
Piston Pump
is driven by the
engine and powers the hydraulic
traction drive motor.
oot e al
ro ac
an
otar Sensor
The foot pedal actuates the
Push/Pull Control Cable
which
is connected to the
Hydroback
Centering Unit
.
The
Hydroback Centering Unit
transfers the
Push/Pull Control Cable
motion to the
Piston Pump Lever Weldment
attached to the
Piston Pump
to control machine direction and speed. The
Hydroback Centering Unit
also returns
the foot pedal and
Piston Pump Lever Weldment
to the neutral position when the foot pedal is released.
The
Rotary
(Drive Pedal)
Sensor
is a 0 to 5K ohm potentiometer that rotates with the
Piston Pump Lever
Weldment
. The resistance through the
Rotary Sensor
will vary with the position of the
Piston Pump Lever
Weldment
. The Driver Box monitors the voltage through
Rotary Sensor
to ensure that the foot pedal is in
neutral before the engine can be started, and to actuate the scrub/sweep functions when the foot pedal is
moved from the neutral position.
Piston Pump
Lever
Weldment
Piston
Pump
Rotary
Sensor
Hydroback
Centering
Unit
Push/Pull
Control
Cable
Piston Pump
Lever
Weldment