MAINTENANCE AND SERVICE 21
FAULT
CAUSE
REMEDY
Pump running normally but
pressure low on installation
Inlet Filter blocked or dirty
Pump sucking air
Valves sticking
Unloader valve seat faulty
Check & Clean Inlet Filter
Check water supply &
possibility of air ingress.
Check & clean or replace.
Check & replace if required.
Pump running normally but
pressure low on installation
Inlet Filter blocked or dirty
Nozzle incorrectly sized
Worn piston packing
Check & Clean Inlet Filter
Check & replace if required
Check & replace if required
Fluctuating pressure
Inlet Filter blocked or dirty
Valves worn
Blockage in valve
Pump sucking air
Worn piston packing
Check & Clean Inlet Filter
Check & replace if required.
Check & clean if required.
Check water supply & air
ingress at joints in suction
line.
Check & replace if required.
Pressure low after period of
normal use
Inlet Filter blocked or dirty
Nozzle worn
Suction or delivery valves
worn or blocked
Worn piston packing
Check & Clean Inlet Filter
Check & replace if required.
Check & replace if required.
Check & replace if required.
Pump noisy
Inlet Filter blocked or dirty
Air in suction lines
Broken or weak suction or
delivery valve springs
Foreign matter in the valves
Worn bearings
Excessive temperature of
water
Check & Clean Inlet Filter
Check water supply &
connections in suction line.
Check & replace if required.
Check & clean if required.
Check & replace if required.
Reduce below 75
centigrade.
Presence of water in the oil
Oil seals worn
High Humidity in the air
Piston packing worn
Check & replace if required.
Check & reduce oil change
intervals.
Check & replace if required.
Water dripping from below
pump
Piston packing worn
Plunger retainer O ring worn
Leaking connections
Check & replace if required.
Check & replace if required.
Check & tighten or reseal.
Oil dripping
Oil seal worn
Check & replace if required.
Excessive vibration in the
delivery line
Inlet Filter blocked or dirty
Valves probably blocked
Check & Clean Inlet Filter
Check & clean if necessary.
Engine will not start
Switch in correct position
Fuel line is switched off.
Battery flat
Oil Alert activated (if fitted)
Check & correct.
Check fuel line & tank.
Check battery connections.
Check engine oil level.
No water from nozzle
Inlet Filter blocked or dirty
Unloader in constant by-
pass
Blocked nozzle
Check & Clean Inlet Filter
Check & turn knob to
pressure.
Check & clean if necessary.
