
Operation
308156S 9
Operation
Pressure Relief Procedure
Follow the Pressure Relief Procedure whenever
you see this symbol.
1. Shut off the hydraulic power supply.
2. Close the supply line shut-off valve (L, FIG. 2).
3. Open the dispensing valve to relieve pressure.
4. Open the pump outlet drain valve and have a con-
tainer ready to catch the drainage.
5. Close the return line shut-off valve (H).
NOTE: Leave the drain valve open until you ar ready to
dispense again.
If you suspect that the nozzle or hose is completely
clogged, or that pressure has not been fully relieved
after following the steps above, very slowly loosen the
hose end coupling to relieve pressure, then clear the
obstruction.
Before Starting the Pump
1. Check the hydraulic fluid level in the hydraulic power
supply before each use, and add fluid as necessary
to fill the lines.
2. Flush the pump before you use it for the first time to
remove the light oil that was left in after factory test-
ing to protect the pump from corrosion. Be sure the
solvent used is compatible with the fluid to be
pumped and the pump wetted parts. See Technical
Data, page 24. Flush until clean solvent comes from
the outlet hose.
To Start the Pump
1. Turn on the hydraulic power supply.
2. Open the return line shut-off valve (H), and slowly
open the hydraulic supply shut-off valve (L).
3. Adjust the flow control valve (R) to limit the hydraulic
flow to no more than 3 gpm (11 lpm), which is
approximately 60 cycles per minutes.
NOTE: If Graco Part No. 236864 hydraulic fluid control
is used, no adjustment is necessary.
4. By adjusting the pressure reducing valve (N), adjust
the hydraulic inlet pressure from 50 to 1500 psi
(0.34 to 10.2 MPa, 3.4 to 102 bar). Increasing the
inlet pressure increases the outlet pressure.
Decreasing the inlet pressure decreases the outlet
pressure.
5. Always use the lowest pressure possible to obtain
the desired results. This reduces pump wear.
This equipment stays pressurized until pressure is
manually relieved. To help prevent serious injury from
pressurized fluid, such as skin injection, splashing
fluid and moving parts, follow the Pressure Relief
Procedure when you stop spraying and before
cleaning, checking, or servicing the equipment.
NOTICE
Always use Graco approved hydraulic oil or equiva-
lent, Part No. 169236 (5 gallon) or 207428 (1 gallon).
Do not substitute lower grade oil.
NOTICE
Never allow a pump to run dry of the fluid being
pumped. A dry pump quickly speeds up and can
damage itself. If it speeds up, shut off the power sup-
ply to the reciprocator immediately. Refill the supply
container, and prime the pump to eliminate air.