Troubleshooting
334606E
31
Displacement pump operates,
but output is low on down stroke
and/or on both strokes
Piston packings worn or
damaged
Tighten packing nut or replace
packings. See manual 334654
Intake valve ball check not
seating properly
Service intake valve ball check.
See manual 334654
Suction tube air leak
Hydraulic oil filter is dirty
Replace filter.
Paint leaks and runs over side of
wet cup
Loose wet cup
Tighten wet cup enough to stop
leakage
Throat packings worn or
damaged
Replace packings. See manual
334654
Excessive leakage around
hydraulic motor piston rod wiper
Piston rod seal worn or
damaged
Replace these parts. See
manual 334654
Fluid delivery is low
Pressure setting too low
Increase pressure, page 18
Displacement pump outlet filter
(if used) is dirty or clogged
Clean or replace.
Contractor gun filter (if used) is
dirty or clogged
Clean or replace.
Intake line to pump inlet is not
tight
Tighten.
Hydraulic motor is worn or
damaged
Bring sprayer to Graco
distributor for repair.
Large pressure drop in fluid
hose
Reduce length or increase
diameter.
The sprayer overheats
Paint buildup on hydraulic
components
Clean
Oil level is low
Fill with oil. See page 16
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
Pump noise
Low hydraulic fluid level
Turn sprayer OFF. Add fluid*.
See page 16
Electric motor does not operate
Power switch is not ON
Turn power switch ON
Tripped circuit breaker
Check circuit breaker at power
source. Reset motor switch
*Check hydraulic fluid level often. Do no allow it to become too low. Use only Graco hydraulic fluid, page 16.
Problem
Cause
Solution
