Graco Ultra 1000 - Page 29

29
307–785
PRESSURE CONTROL REPLACEMENT
Before doing this procedure, follow the Pressure
Relief Procedure Warning on page 24 to reduce
the risk of a fluid injection injury , splashing in the
eyes or on the skin, injury from moving parts, or
electric shock. Unplug the sprayer!
WARNING
Refer to Fig 29–1 except where noted.
1. Disconnect the main fluid hose (101) and the secon -
dary fluid hose, if used. Disconnect the fluid hose
(70) at the displacement pump nipple (40) and the
pressure
control nipple (344).
2. Loosen the filter bracket nut (38).
3. Hold the hex of the pressure control adapter (341)
firmly with a 3/4” open end wrench. Use an adjust-
able wrench to unscrew the swivel union (39), and
then
remove the fluid filter (66).
4. Remove the pressure control cover (63). Disconnect
the four motor leads. Refer to Fig 28–2.
5. Remove the circuit board and retain it. Refer to page
28.
6.
Remove the conduit (1).
7.
Remove the three screws (8) and lockwashers (10)
and
nuts (1 1) located below the pressure control. Re -
move
the pressure control.
8. Remove the screws (22) holding the back mounting
bracket (64) to the pressure control.
9. Install the new pressure control assembly in the re-
verse order of disassembly . Reinstall the conduit
seal (29) around the wires in the conduit connector
(345) to prevent motor contamination from entering
the
control. See the DET AIL below .
10. Perform the PRESSURE CONTROL ADJUST-
MENT, page 30, before regular operation of the
sprayer.
CAUTION
Do not allow the adapter (341) to turn while installing
the new pressure control assembly . Turning it can
damage the sensitive bourdon tube. Hold the
adapter firmly with a 3/4” open end wrench while
screwing
in the swivel union (39).
341
Fig 29–1
39
70
1
36,63
64
22
38
12
11
10
8
40
344
345
CAUTION
Do not allow the adapter
(341) to turn at any time.
DETAIL
Shows position of con -
duit seal (29) in conduit
connector (345)
29
345