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12
307-863
Flushing
NOTE: Several flushes are often required to thoroughly clean the system and prepare it for the next fluid to be
sprayed, or to store the sprayer. Use this chart to determine the required flushing order for the fluid you are using,
and then follow the procedure below for flushing.
*Use this category for flushing a brand new sprayer and flushing after storage.
System has
this fluid in it:
Next fluid to be
sprayed
Flushing order:
Before you spray or store
sprayer:
this fluid in it:
sprayed.
Flush 1
Flush 2
Flush 3
sprayer:
*Oil-based
solvent or paint
Oil-based paint –
new color
Mineral spirits
none
none
Prime with oil-based paint
Oil-based
solvent or paint
Water-based paint
Mineral spirits
Warm soapy
water
Clean water
Prime with water-based
paint
Oil-based
solvent or paint
Prepare for
storage
Mineral spirits
none
none
Relieve pressure,
Leave drain valve open
Water or water-
based paint
Water-based paint
– new color
Warm soapy
water
Clean water
none
Prime with water
Water or water-
based paint
Oil-based paint
Warm soapy
water
Clean water
Mineral spirits
Prime with oil
Water or water-
based paint
Prepare for
storage
Warm soapy
water
Clean water
Mineral spirits
Relieve pressure,
Leave drain valve open
CAUTION
NEVER allow water to freeze in the pressure control.
Doing so prevents the sprayer from being started and
causes serious damage to the pressure control.
Pump the water out with mineral spirits.
WARNING
To reduce the risk of static sparking and splashing
when flushing, always remove the spray tip from
the gun and hold a metal part of the gun firmly to
the side of a grounded metal pail.
1.
Follow the illustrated Pressure Relief Procedure
on page 2. Engage the gun safety latch.
2.
Turn the pressure adjusting knob fully counter-
clockwise to the minimum pressure.
3.
Remove the spray tip from the gun. Remove the
filter bowl (A) and screen (B); see manual
307–273. Clean the screen separately and install
the bowl without the screen to flush it. See Fig. 4.
4.
Put the suction tube into a grounded metal pail
with 1/2 gallon of compatible solvent.
5.
Start the sprayer. See page 10. To save the fluid in
the sprayer, trigger the gun into another container
until the next fluid appears, then trigger the gun
back into the fluid you are pumping. Circulate the
flushing fluid to thoroughly clean the system.
6.
Remove the strainer (and suction tube, if used) and
clean separately to remove all paint sediment.
7.
Do not run the pump dry for more than 30 seconds
to avoid damaging the pump packings!
8.
Follow the illustrated Pressure Relief Procedure
on page 2. Engage the gun safety latch.
9.
Unscrew the filter bowl and reinstall the clean
screen. Install the bowl and hand tighten. Install
the suction tube assembly.
Fig. 4
0142
A
B
C
53