Versalift VST-9000I-E100, Service And Installation Manual

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103-21 VERSALIFT VST-9000-I-E
SER
VICE PROCEDURES
ROTATION MOTOR COUNTERBALANCE VALVES
-
The rotation motor counterbalance valves are
located in a manifold mounted to the motor.
1. Unbolt the rotation motor and disengage it from
the rotation gearbox.
2. Tee 3000-psi (minimum) pressure gauges
into each of the two motor ports, as shown on
diagram.
3. It is necessary to set the holding-valve pilot-
pressure to obtain smooth rotation while
maintaining adequate rotation speed. The
higher the pressure setting, the more restrictive
the valves are, providing smoothest operation.
However, as the pressure is increased, a
reduction in rotation speed may occur. The
suggested pressure range is 1100 psi plus or
minus 200 psi. Adjustments can be made on the
pressure setting to obtain smooth operation on
a slope and adequate rotation speed on level
ground. Do not exceed 1300 psi. Excessive
backpressure can adversely affect the life of the
motor shaft seal.
4. Start the unit and, from the lower controls, fully
actuate the rotation control for clockwise (CW)
rotation. Read the pressure gauge opposite the
clockwise (CW) port and set the pressure to
1100 psi. To adjust the pressure setting, loosen
the lock nut on the top of the cartridge opposite
the clockwise (CW) port, and with a 1/8 inch allen
wrench turn the set screw counter-clockwise
(CCW) to increase the pressure setting, and
clockwise (CW) to decrease. Return the control
to neutral and actuate again to verify pressure
setting. Next fully actuate the rotation control for
counter-clockwise (CCW) rotation and adjust the
cartridge opposite the counter-clockwise (CCW)
port to 1100 psi, in the same manner as before.
Tighten the lock nuts after adjusting.
5. Remove the pressure gauge and reconnect the
hoses to the motor. Install and bolt the motor to
the gearbox.
6. Start the unit and verify that the direction of
rotation is correct. Reverse hose connections
at the rotation motor if required. Verify smooth
operation on a slope and adequate rotation
speed on level ground.
BOOM ACTUATION SPEED - The boom actuation
speed is controlled by the system operating pressure
and the pump or engine speed. Refer to “System
Operating Pressure” in this section for the proper
adjustment procedure of this function. A fl ow meter
can be installed in the tool circuit to measure the
fl ow rate. If the proper PTO has been installed,
the maximum fl ow rate of 10 gpm (38 lpm) can be
provided by adjusting the engine speed. Another
method of verifying proper boom actuation speeds
is to time one cycle with an operator in the platform.
The recommended range for each boom actuation for
the unit is given below. These times are approximate
and may vary with platform load, boom position, and
other factors.
Rotation (CW or CCW) 90-105 Seconds
Outer Boom (Raise) 40-50 Seconds
(Lower) 30-40 Seconds
Lower Boom (Raise) 50-60 Seconds
(Lower) 35-45 Seconds
Inner Boom (Extend) 40-50 Seconds
(Retract) 30-40 Seconds
Exercise care when timing boom functions, to avoid
reaching the end of boom travel while at full operating
speed.
To accurately test the flow rate or lift actuation
speeds, it is critical for the hydraulic oil to be warmed
to operating temperatures between 70°F and 90°F
(21°C and 32°C). Cold hydraulic oil will result in
slow operation with increased engine speed having
no affect. The engine speed, whether controlled by
a manual throttle or an optional two speed throttle
control, should be regulated to provide speeds within
the specifi c ranges given for each function. To aid in
warming the hydraulic oil, select the warm up mode
to allow oil to circulate.