Figure 9-40.—Remote hand throttle assembly.
4. The loader is equipped with a remote hand
throttle assembly (fig. 9-40) located on the front cover
of the loader, which is behind the backhoe operator’s
seat. The hand throttle is preset to the backhoe
specifications to deliver the proper amount of hydraulic
oil flow for backhoe operations. The speed of the engine
determines the volume of hydraulic oil delivered to the
backhoe and the speed of the cylinder movements.
Because of this, you should set the engine at a low speed
until you are familiar with the control lever pattern.
NOTE: The backhoe is designed to operate effi-
ciently at a preset gallons per minute flow of hydraulic
fluid. Setting the engine throttle in excess of that set for
backhoe operations creates excessive hydraulic
temperatures and pressures that can damage hydraulic
and structural components.
5. Lower the backhoe stabilizer legs to fix the
backhoe in position.
6. Warm up the backhoe hydraulic system by
extending and retracting each hydraulic cylinder piston
rod several times to circulate warm oil through the
hydraulic system. When the backhoe hoses feel warm
when touched, the backhoe is ready for operation.
WARNING
Before performing maintenance on the
backhoe, you must extend the dipper stick fully
and set the bucket and stabilizer on the ground.
Shut down the engine, and actuate all of the
control levers back and forth to relieve the
hydraulic pressure in the system.
Loader Backhoe
The loader backhoe tractor (fig. 9-41) is equipped
with a 1.3-cubic-yard bucket mounted on the front and
the backhoe mounted on the rear.
The loader is equipped with a four-speed transaxle
that permits the gears to be shifted from first or second
to third or fourth and back again to third without
stopping. When shifting gears, always make sure the
engine speed remains in the green area of the
tachometer.
The loader also has a differential lock that gives
equal power to both rear wheels when the machine is
stuck or before the loader is operated through a soft or
muddy area. When the loader is stuck, the differential
lock is actuated as follows:
1.
2.
3.
4.
5.
Make sure the rear wheels are not turning.
Push down the clutch cutout pedal (fig. 9-42).
Push down the differential lock pedal.
Release the clutch cutout pedal.
Increase the engine speed and release the
differential lock pedal.
NOTE: The differential lock releases automatically
when the load is removed.
9-16
