Stellar Industries 28000 - Manual (Page 52)

48 28000 Owner’s Manual
Problem: Cylinder drifts outward or
downward.
Solutions:
• Check to see if there is air in the hydraulic
system. Operate all cylinders connected to
the hydraulic system. Start with the extension
cylinder, then operate the main boom, winch,
rotation, and ending with the hydraulic
outriggers, if installed. When operating,
extend each cylinder halfway out, retract all
the way in, and then extend until the cylinder
rod is at the end of its stroke. Operate
cylinders slowly so air is pushed thru the
system to the reservoir. Repeat this cycle 2-3
times.
• Make sure the holding valves are operating
properly. Remove, clean, and then inspect
each holding valve. When removing a
holding valve, always relieve the pressure
inside the cylinder by loosening jam nut of the
holding valve and turning set screw
inward/clockwise. Count the number of turns
until the set screw is seated. When
reinstalling the holding valve, make sure the
valve is reset by turning the set screw the
number of turns it took to relieve the
pressure. Finish by tightening the jam nut.
• Check the cylinder rod for scratches. If a
scratch is located on the cylinder rod,
hydraulic fluid can pass thru and cause a loss
Problem: Not all crane functions operate
using the radio remote transmitter or crane
operates intermittently.
Solutions:
• Make sure that the function switch is working
properly. If the switch is defective, simply
replace it.
• Make sure that there is power going from the
valve bank twin solenoid or to the function
that will not operate. If no power is going to
the twin solenoid, check wiring connections
on wire harness plug connector for broken
wires, loose connection or poor crimp. If
power is going to the solenoid valve, it may
not be opening to allow hydraulic oil to the
function that is not operating. Check the twin
solenoid for polarity, if solenoid does not
magnetize, replace the twin solenoid.
Problem: Outer “Extend” and Extension In and
Out will not operate Manually or Remotely.
Solutions:
• Check to see if the functional cut out connector,
located on the valve section is lit. Note:
Functional cut out connectors will have an LED
light on when electrical power is present
• Check to see if there is 12 volt power going to
functional cut out connector.
• Check to make sure the Bosch relay is
functioning properly. It is located just behind
the panic bar E-stop switch. If functional cut out
connector is lighting properly, check to make
sure the connector is tight.
Problem: Single crane function will not
operate (Will not pressurize), because the
valve section shuttle ball is not releasing.
Solutions:
• Locate a different valve section further down
stream from the valve section that is not
functioning. Note: Use a function other than
any rotation sections such as crane rotation,
tireman rotation, or pad rotation. Operate the
valve section or crane function further down
stream from the faulty valve section. Extend
the cylinder or cylinders until full extension is
achieved and hold. While holding that function,
operate the faulty valve section function, then
quickly release the handle assembly of the
valve section that was being held. By
pressurizing the the function further down
stream and quickly releasing the handle, the
back pressure should release the shuttle ball
on the faulty valve section. This may not work
the first time so repeat the above procedure
until the faulty function operates properly.
of pressure. Replace cylinder rod or cylinder.
• Check to see if the piston seals are damaged.
If they show signs of damage, install a new
cylinder seal kit.