Allmand Brothers TLB6235 Tractor - Manual (Page 26)

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Clean the bucket by hand, if at all possible. If rapping the bucket against the stops is the only
option, then do so using MINIMUM force, to prevent cylinder damage.
DO NOT try removing stuck material from the bucket by striking it against the ground or
another object.
PREPARING TO OPERATE BACKHOE
1. Position loader bucket flat on the ground. Lower loader arms to raise wheels off the
ground.
2. Engage park brake.
3. Switch seats to position operator facing the backhoe.
4. Lower stabilizers to level unit.
5. Disengage swing lock and backhoe boom lock.
PREPARING TO OPERATE LOADER AFTER OPERATING BACKHOE
1. Retract backhoe bucket and dipperstick functions. Raise backhoe boom.
2. Center boom and engage boom lock.
3. Raise stabilizers.
4. Switch seats to position operator facing the front end loader.
Roll back loader bucket until bottom is parallel with the ground.
The purpose of the dump valve is to allow the movement of a disabled vehicle or if you have
a vehicle that you just want to push a short distance, without starting the engine. When a
hydrostatic driven vehicle is shut down’ it is virtually impossible to move the vehicle without
opening the hydrostatic
closed loop circuit.
If an attempt is made to push the vehicle the
hydraulic motor be- comes a pump,
trying to pump oil to the hydrostatic pump.
This creates a hydraulic lock between the
motor and the pump. To overcome this
condition, a dump valve has been installed
between the high pres- sure relief valves in
the backplate of the pis- ton pump. The
dump valve is a plug that contains a rotating
stem which has a flat spade end that fits
between the two ends of the high pressure
relief valves. When the dump valve is in the
“closed position”, the relief valves are
also in the closed posi- tion
as shown in the top illustration. When the dump valve stem is ro- tated
90 degrees, the flat spade end spreads the relief valves to the “open posi-
tion” as shown in the lower illustration. This allows the oil in the hy- dro-
static closed loop to “by-pass” around the high pressure relief valves in-
side the pump backplate. The by-passing of oil inside the pump
backplate will allow the motor to rotate freely when the vehicle is
moved a short distance. The dump valve is intended only for mov-
ing a
vehicle a very short distance and not intended for towing a vehicle behind a truck or tractor.
NOTE: serious damage to the hydrostatic drive will result if vehicle is towed. The
dump valve must be completely closed prior to normal operation of the vehicle.
HYDROSTAT DUMP VALVE OPERATION