Troubleshooting, Warning – Hitachi HYDRAMAX 309379 User Manual
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5
309379
Troubleshooting
WARNING
INJECTION HAZARD
To reduce risk of serious injury, when instructed to relieve pressure, follow steps 1. – 6.; page 4.
PROBLEM
CAUSE
SOLUTION
Gas engine pulls hard (won’t start)
Hydraulic pressure is too high
Turn hydraulic pressure knob ccw to lowest setting
Gas engine will not start
Switch OFF, low oil, no gasoline
Consult engine manual, supplied
Gas engine races to high rpm at
stall – bogs down on operation
Engine governor worn
Contact Honda Engine Service Center
Gas engine operates, but
displacement pump does not
Directional valve not switching
Turn pump switch OFF, then ON; manual 309379
Pump switch is OFF
Turn pump switch ON
Pressure setting too low
Increase pressure, manual 309378
Displacement pump outlet filter (if
used) is dirty or clogged
Clean the filter
Tip or tip filter (if used) is clogged
Remove tip and/or filter and clean
Hydraulic fluid too low
Shut off sprayer immediately. Add fluid*; page 4.
Hydraulic pump worn or damaged
Bring sprayer to Graco distributor for repair
Displacement pump rod seized by
dried paint
Service pump; manual 309277
Displacement pump stays in down-
stroke
Powered off sprayer with engine ON/
OFF. Magnet below bottom sensor.
Start engine. Turn pump switch OFF, then ON. In-
crease pressure.
Displacement pump operates, but
output is low on upstroke
Piston ball check not seating properly.
Piston packings worn or damaged.
Service piston ball check; manual 309277.
Replace packings; manual 309277.
Displacement pump operates but
output is low on downstroke and/
or on both strokes
Piston packings worn or damaged.
Intake valve ball check not seating
properly.
Remove clip and retighten or replace packings;
manual 309277.
Service intake valve ball check; manual 309277
Paint leaks and runs over side of
wetcup
Loose wet–cup
Throat packings worn or damaged
Tighten just enough to stop leakage
Replace packings; manual 309277
Excessive leakage around
hydraulic motor piston rod wiper
Piston rod seal worn or damaged
Replace these parts; manual 309379
Fluid delivery is low
Pressure setting too low
Displacement pump outlet filter (if
used) is dirty or clogged
Intake line to pump inlet is not tight
Hydraulic motor is worn or damaged
Large pressure drop in fluid hose
Increase pressure, manual 309378
Clean filter
Tighten
Bring sprayer to Graco distributor for repair
Use larger diameter hose
The sprayer overheats
Cooler is damaged
Replace
Oil level is low
Fill with oil. See page 6.
Spitting from gun
Air in fluid pump or hose
Check for loose connections on siphon assembly,
tighten, then reprime pump
Loose intake suction
Tighten
Fluid supply is low or empty
Refill supply container
DTS does not display
Loose wiring
Remove cover and correct poor connections
Bad LCD or board
Bring sprayer to Graco distributor for repair
DTS displays error codes
Various over-pressure conditions
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*Check hydraulic fluid level often. Do not allow it to become too low. Use only Graco approved hydraulic fluid, page 4.