FIGURE 8
The variable displacement pump has a neutral position in which no fluid is pumped to the motor. Moving the travel
control lever on the operator's console to either side of neutral, while the engine is running, causes oil to be pumped to
the motor, one side turning the motor in forward travel and the other side in reverse travel. The further the control lever is
moved from neutral position, the faster the Roller will travel Changing the engine throttle speed will also change the
Roller speed providing the pump control lever is not in neutral position. If lever is in neutral position, the Roller will not
move.
3. Power Steering. Figure 9 . This system consists of a rotor type pump mounted to a bracket on the engine and belt
driven off the engine fan pulley, an "Orbitrol" steering unit, double acting hydraulic cylinder and suit- able hydraulic hoses
Turning the steering wheel to the right causes the oil under pump pressure, through the "Orbitrol" unit, to flow to the
cylinder bottom, forcing the cylinder piston rod to extend out of the cylinder and in turn forces the roll to be turned to the
right Turning the steering wheel to the left causes oil to flow to the top of the cylinder, forcing the piston down, thus
pulling the roll to the left
FIGURE 9
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