Troubleshooting - Graco Power-Star 236754 Instructions Manual

Troubleshooting

Troubleshooting
Problem
Pump will not run
Pump speeds up or runs erratically
Pump runs, but output low on up
and/or down strokes
Excessive weepage from porous
plug (B)
Hydraulic oil leaks from seal nuts in
the upper housing or cap (36, 43)
Pump runs slowly with dispense
valve closed
10
1. Follow Pressure Relief Procedure, page 8, before
checking or repairing gun.
2. Check all possible problems and causes before dis-
assembling gun.
Cause
Closed dispense valve
Pressure too low
Insufficient hydraulic fluid supply
Clogged fluid outlet line, intake
valve, dispense valve, suction line
Motor stalled
Reciprocator damaged
Pump piston and/or intake valve
worn
Empty supply container
Pump piston and/or intake valve
worn
Insufficient material fluid supply
Pressure too low
Clogged fluid outlet line, intake
valve, dispense valve, suction line
Worn throat seals
Seal nuts (19) are loose, worn, or
damaged
Pump/dispense line leakage
Solution
Pump only runs with valve open.
Increase supply pressure using the
pressure adjusting valve.
Check hydraulic power supply.
Adjust to a maximum of 12 gpm
(45.4 lpm) flow
Check; clear obstructions.
Press reciprocator reset button (39).
Pump should start immediately. See
Parts Drawing on page 16.
Repair. See pages 11 through 15.
Check and repair. See Page 11
Refill and reprime. Do not allow
pump to run dry. Monitor closely or
use a low-level cutoff valve.
Check and repair. See Page 11.
Refill fluid supply container.
Increase supply pressure using the
pressure adjustment on the control.
Check; clear obstructions.
Repair. See page 11
Tighten the seal nuts. If leaking per-
sists, change the seal nuts.
If system is OK, rebuild the pump.
Use kits 220457 and 236862.
308391K