Hardi FTZ Force Boom, Operator And Maintenance Manual

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6 - Troubleshooting
Boom hydraulic system
Fault Possible cause Suggested action
No boom movement Insuffi cient hydraulic pressure. Check oil pressure-
min. 130 bar
max. 160 bar
Check tractor
hydraulic oil level.
Insuffi cient oil supply. Oil fl ow must be
min.10 l/minute
max. 90 l/minute.
Check tractor
hydraulic oil level.
Insuffi cient power supply. Voltage on activated
solenoid valve must
be more than 8 Volts
Use wires of at
least 4 mm diam.
No boom movement Defective relay or diodes in junction box. Check relays, diodes
and soldering at PCB
in junction box.
Clogged restrictors in by-pass block. Remove and clean
restrictors a and b in
bypass block (See
hydraulic diagram)
Change hydraulic oil
and fi lter.
Wrong polarity. White pos. (+)
Blue neg. (-).
Boom lift raises to max. pos. when Wrong oil inlet to by-pass block. Reverse hydraulic
tractor hydraulics are engaged. snap couplers or
reverse spool valve.
Back pressure in return line exceeds 20 bar. Connect the return
line with free fl ow to
hydraulic oil reservoir.
Divide return line in
two and run oil back
to the reservoir via
two spool valves.
Oil heats up in Closed By-pass valve does not close properly. Check bypass valve
Centre systems. operation.
Internal leaks in fl ow regulator. Replace fl ow regulator
O-rings and back-up
rings.
Troubleshooting
6. 1