Hardi NAVIGATOR VPZ, Instruction Book

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7 - Fault Finding
177
Pump
Hydraulic System, Z-version
FAULT PROBABLE CAUSE CONTROL / REMEDY
Liquid leaks from the bottom of the pump. Damaged diaphragm. Replace diaphragm.
Grease leaks from the bottom of the pump. Grease used has too low viscosity. Change to recommended grease type.
Grease leaks from the shaft grease seals. Grease used has too low viscosity. Change to recommended grease type.
Bearings worn/too high friction. Replace pump bearings and grease seals.
Lack of pressure. Pump valves are clogged or defect. Check for obstructions or, if needed, replace valves.
Clogged filters in fluid system. Clean filters.
Vibrations in system and unpleasant noise from the
pump. Pump valves are clogged or defect. Check for obstructions or, if needed, replace valves.
Air is being sucked into system. Check for leaks, pinholes in suction hoses, tightness /
gaskets / O-rings of all fittings on the suction side.
Lack of flow / capacity. Internal wear on conrod and conrod ring. Poor greasing. Replace parts as needed and observe
proper grease quality and intervals.
Pump valves are clogged or defect. Check for obstructions or, if needed, replace valves.
Extreme internal erosion on diaphragm covers and
housing. Too high vacuum caused by clogged suction filter or
excessive pump speed (rpm). Replace affected pump parts.
Clean suction filter and observe maximum pump
speed (rpm).
Lack of internal cleaning. Use recommended cleaning procedures and add
extra cleaning agents (e.g. AllClearExtra or similar).
Lack of conservation of the fluid system during
storage. Always use a proper mixture of antifreeze during
storage.
Short lifetime for diaphragm. Overspeeding of the pump. Observe maximum pump speed (rpm).
Too high vacuum when filling from external source:
Hose dimension is too small. Fit a larger hose to the External Filling Device.
Too long filling hose. Park sprayer closer to the external tank and use a
shorter hose.
Bad filling conditions, e.g. too high water column
when transferring water from a buried tank. Change external water supply to obtain a lower
water column.
FAULT PROBABLE CAUSE CONTROL/REMEDY
No boom movements when activated. Insufficient hydraulic pressure. Check oil pressure.
Check tractor hydraulic oil level.
Insufficient oil supply. Oil flow must be 15 - 80 l/min (depending on the
equipment on the sprayer).
Check tractor hydraulic oil level.
Blown fuse(s). Check / replace fuse in junction box.
Bad / corroded electrical connections. Check / clean connections, multi plugs etc.
Insufficient power supply. Voltage on activated solenoid valve must be more
than 8 volts.
Use wires of at least 4 mm for power supply.
Defective relay / diodes in junction box. Check relays, diodes and soldering at PCB in junction
box. LED diodes indicate boom functions.
Clogged restrictors in bypass block. Remove and clean restrictors in bypass block (See
hydraulic diagram). Change hydraulic oil + filter.
Wrong polarity. Check polarity. Red positive (+), black negative (-).
ParaLift lock does not lock.
Boom lift raises to max. position, when tractor
hydraulics are engaged.
Back pressure in return line exceeds 15 bar. Connect the return line with a free flow to hydraulic
oil reservoir.
Divide return line in two and lead return oil back to
reservoir via two spool valves.
Oil heats up in Closed Centre systems. Bypass valve does not close properly. Check / close (screw in) by-pass valve.
Internal leaks in flow regulator. Replace flow regulator O-rings and backup rings.
Replace flow regulator.
Individual hydraulic piston does not move. Clogged restrictor. Dismantle and clean restrictor.