Graco PrecisionFlo 233678 Operation manual

Instructions – Parts List
GRACO INC. P.O. BOX 1441 MINNEAPOLIS, MN 55440–1441
Copyright 2001, Graco Inc. is registered to I.S. EN ISO 9001
PrecisionFlo t
Metering Valve Upgrade
3500 psi (24 MPa, 240 bar) Maximum Working Fluid Pressure
For use when dispensing fluids that meet at least
one of the following conditions for non-flammability:
DThe fluid has a flash point above 140_F (60_C)
and a maximum organic solvent concentration of
20%, by weight, per ASTM Standard D93.
DThe fluid does not sustain burning when tested per
ASTM Standard D4206 Sustained Burn Test.
Part No. 233678
PrecisionFlo Metering Valve for PVC application
Part No. 233679
PrecisionFlo Metering Valve for HemFlange application
Table of Contents
Symbols 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Warning 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Operation and Maintenance 5. . . . . . . . . . . . . . . . . . . .
Pressure Relief Procedure 5. . . . . . . . . . . . . . . . . . .
Operating the Metering Valve 5. . . . . . . . . . . . . . . . .
Maintenance 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Service 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Troubleshooting the Metering Valve 6. . . . . . . . . . .
Fluid Needle and Seat Assembly Service 7. . . . . .
Closer Service 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Replacing the Pressure Sensor 11. . . . . . . . . . . . . .
Wiring Diagram 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Parts 14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Part No. 233678, Metering Valve Assembly 15. . . .
Part No. 233679, Metering Valve Assembly 16. . . .
Part No. 233590, Closer Assembly 17. . . . . . . . . . .
Technical Data 19. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Related Publications 19. . . . . . . . . . . . . . . . . . . . . . . . .
Graco Standard Warranty 20. . . . . . . . . . . . . . . . . . . . .
Graco Information 20. . . . . . . . . . . . . . . . . . . . . . . . . . . .
309384 rev.C
TI1394A
Important Safety Instructions
Read all warnings and instructions in
this manual. Save these instructions.
Parts

2 309384
Symbols
Warning Symbol
WARNING
This symbol alerts you to the possibility of serious
injury or death if you do not follow the instructions.
Caution Symbol
CAUTION
This symbol alerts you to the possibility of damage to
or destruction of equipment if you do not follow the
instructions.
WARNING
SKIN INJECTION HAZARD
Spray from the dispensing device, hose leaks, or ruptured components can inject fluid into your body
and cause extremely serious injury, including the need for amputation. Splashing fluid in the eyes or
on the skin can also cause serious injury.
DFluid injected into the skin might look like just a cut, but it is a serious injury. Get immediate surgi-
cal treatment.
DDo not point the dispensing device at anyone or at any part of the body.
DDo not put hand or fingers over the front of the dispensing device.
DDo not stop or deflect fluid leaks with your hand, body, glove, or rag.
DFollow the Pressure Relief Procedure on page 5 whenever you: are instructed to relieve pres-
sure; stop dispensing; clean, check, or service the equipment; or install or clean a spray tip or
nozzle.
DTighten all the fluid connections before operating the equipment.
DCheck the hoses, tubes, and couplings daily. Replace worn, damaged, or loose parts immediately.
Permanently coupled hoses cannot be repaired; replace the entire hose.
FIRE, EXPLOSION, AND ELECTRIC SHOCK HAZARD
Improper grounding, poor air ventilation, open flames, or sparks can cause a hazardous condition and
result in fire or explosion and serious injury.
DThe system must only be installed and serviced by a qualified electrician.
DGround the equipment and the object being sprayed. The Metering Valve is grounded through
proper connection of the two electrical cables.
DDo not install the Metering Valve in a hazardous area, as defined in Article 500 of the National
Electrical Code (USA).
DKeep the dispensing area free of debris, including solvent, rags, and gasoline.
DDo not smoke in the dispensing area.
DIf there is any static sparking while using the equipment, stop dispensing immediately. Identify
and correct the problem.
DDisconnect the two electrical cables from the Metering Valve before servicing the valve.

309384 3
WARNING
INSTRUCTIONS
EQUIPMENT MISUSE HAZARD
Equipment misuse can cause the equipment to rupture, malfunction, or start unexpectedly and result
in serious injury.
DThis equipment is for professional use only.
DRead all instruction manuals, tags, and labels before operating the equipment.
DUse the equipment only for its intended purpose. If you are uncertain about usage, call your Graco
distributor.
DOnly use the PrecisionFlo Metering Valve with the PrecisionFlo Control.
DDo not alter or modify this equipment. Use only genuine Graco parts and accessories.
DCheck the equipment daily. Repair or replace worn or damaged parts immediately.
DDo not disassemble the Metering Valve motor. The motor contains powerful magnets, which could
attract metal objects and create a hazardous condition if the motor end plates are removed. Con-
tact your Graco distributor for motor service.
DDo not exceed the maximum working pressure of the lowest rated system component. This equip-
ment has a 3500 psi (24 MPa, 240 bar) maximum working pressure.
DRoute the hoses away from the traffic areas, sharp edges, moving parts, and hot surfaces. Do not
expose Graco hoses to temperatures above 180_F (82_C) or below –40_F (–40_C).
DDo not use the hoses to pull the equipment.
DUse fluids that are compatible with the equipment wetted parts. See the Technical Data section of
all the equipment manuals. Read the fluid manufacturer’s warnings.
DComply with all applicable local, state and national fire, electrical and other safety regulations.
DDo not touch the metal heat sink when the surface is hot.
DDo not cover the Metering Valve; the motor needs air ventilation.
TOXIC FLUID HAZARD
Hazardous fluids or toxic fumes can cause serious injury or death if splashed in the eyes or on the
skin, swallowed, or inhaled.
DKnow the specific hazards of the fluid you are using. Read the fluid manufacturer’s warnings.
DProvide fresh air ventilation to avoid the buildup of vapors from the fluid being dispensed.
DStore hazardous fluid in an approved container. Dispose of hazardous fluid according to all local,
state and national guidelines.
DWear the appropriate protective clothing, gloves, eyewear, and respirator.
MOVING PARTS HAZARD
Moving parts, such as the fluid needle, can pinch fingers. Parts of the Metering Valve are spring-
loaded and parts may fly out or spring apart when the valve is disassembled and cause serious injury,
including eye injuries.
DDo not operate the equipment with the guard removed.
DKeep clear of any moving parts when starting or operating the equipment.
DWear eye protection during all service procedures.

4 309384
Installation
WARNING
ELECTRIC SHOCK HAZARD
Installing and servicing this equipment
requires access to parts which could
cause an electric shock or other serious
injury if the work is not performed properly. Do not
install or service this equipment unless you are
trained and qualified.
NOTES:
DHave the system binder (a collection of manuals
and diagrams in a three-ring binder, supplied by
Graco) available during installation.
DReference numbers and letters in parentheses in
the text refer to the numbers and letters in the
illustrations.
DBe sure all accessories are adequately sized and
pressure-rated to meet the system’s requirements.
DOnly use the PrecisionFlo Metering Valve with the
PrecisionFlo Control.
1. Mount the Metering Valve. See the mounting hole
dimensions in Fig. 1.
2. Connect the fluid supply line to the 3/8–18 npt fluid
inlet (A). See Fig. 2.
3. Connect a fluid line between the 3/8–18 npt fluid
outlet (B) and the dispensing device.
4. Connect the electrical cable (C) to the Metering
Valve connector (E).
5. Connect a 0.25 inch (6.35 mm) O.D. air line be-
tween the closer air inlet (G) and the closer actuat-
ing air valve.
WARNING
FIRE, EXPLOSION, AND ELECTRIC
SHOCK HAZARD
To reduce the risk of fire, explosion, or
electric shock the Metering Valve must
be grounded through proper connection
of the two electrical cables.
A qualified electrician must complete all
grounding and wiring connections.
Fig. 1
05478B
A A= 19.0 in.
(482.6 mm)
B B= 6.913 in.
(175.6 mm)
C C= 7.15 in.
(181.6 mm)
D D= 1.25 in.
(31.8 mm)
E E= 4 in.
(102 mm)
FF = 4 x 1/4–20 in.
FF
EE
AA
BB
DD
CC
TI1394A
Fig. 2
C
E
A
B
G

309384 5
Operation and Maintenance
Pressure Relief Procedure
WARNING
SKIN INJECTION HAZARD
The system pressure must be manually
relieved to prevent the system from
starting or dispensing accidentally. Fluid
under high pressure can be injected through the
skin and cause serious injury. To reduce the risk of
an injury from injection, splashing fluid, or moving
parts, follow the Pressure Relief Procedure
whenever you
DAre instructed to relieve the pressure
DStop dispensing
DCheck or service any of the system equipment
DInstall or clean a spray tip or nozzle
1. Shut off the fluid supply to the Metering Valve.
2. Actuate the Metering Valve and the dispensing
device until the fluid stops flowing from them.
NOTE: Follow the manual purge procedure in the
PrecisionFlo system manual to actuate the meter-
ing valve and dispensing device.
3. Relieve the system pressure as instructed in the
separate instruction manuals.
Operating the Metering Valve
The Metering Valve is operated through the
PrecisionFlo Control. Follow the PrecisionFlo Control
instructions to operate the Metering Valve.
WARNING
MOVING PARTS HAZARD
Moving parts, such as the fluid needle,
can pinch fingers. Do not operate the
equipment with the guard (39) removed.
Maintenance
Visually check the following items periodically:
DCheck the fluid needle and seat area for leakage
and wear.
DCheck the fluid needle shaft for leakage and wear.
DMake sure the fluid connections are tight and are
not leaking.
DCheck the cables for damage and make sure they
are securely connected.
Clean the Fluid Needle and Seat Assembly
If the fluid flow from the dispensing device appears to
be restricted, disassemble the fluid needle and seat as
instructed on page 7 and clean the parts. Use a
non-flammable cleaning fluid that is recommended by
your material supplier.

6 309384
Service
Troubleshooting the Metering Valve
WARNING
EQUIPMENT MISUSE HAZARD
Do not disassemble the Metering Valve motor. The
motor contains powerful magnets, which could
attract metal objects and create a hazardous
condition if the motor end plates are removed.
Contact your Graco distributor for motor service.
WARNING
MOVING PARTS HAZARD
Parts of the Metering Valve are spring-
loaded and parts may fly out or spring
apart when the valve is disassembled
and cause serious injury, including eye injuries.
Wear eye protection during all service procedures.
Follow the instructions, paying special attention
when you see the Moving Parts Hazard symbol in
this warning.
1. If the fluid continues to flow after the dispense
cycle has stopped, check for the following prob-
lems:
a. The fluid needle may be obstructed or dam-
aged. Service the fluid needle as instructed on
page 7.
b. The seat or seals may be worn or damaged.
Service the fluid needle as instructed on
page 7.
c. Check that the PrecisionFlo Control on/off
delay is set properly. See the chart for the
applicable PrecisionFlo Control Assembly
manual.
Form P/N Title
310531 918463 * PrecisionFlotControl
Abl
918644 ‡ Assembly
* Hand pendant ‡ Door Pendant
§ Single Application
2. If the pressure sensor needs replacement, follow
the procedure on page 11.
3. Refer to the wiring diagram in Fig. 8, page 12, for
cable wire connections.

309384 7
Service
Fluid Needle and Seat Assembly Service
WARNING
SKIN INJECTION HAZARD
To reduce the risk of an injury, including
an injection injury, follow the Pressure
Relief Procedure on page 5 before
checking or servicing the equipment and whenever
you are instructed to relieve pressure.
NOTE: Adjusting the fluid needle is not necessary after
installing the PrecisionFlo Upgrade.
1. Relieve the pressure in the system.
2. Disconnect the electrical cable (C) from the meter-
ing valve connector (E). See Fig. 2 on page 4.
3. Disconnect the fluid lines from the metering valve
fluid inlet (A) and outlet (B). See Fig. 3.
4. Disconnect the closer air line from the closer air
inlet (G).
5. Unmount the metering valve and take it to a clean
work area with a compressed air supply.
6. Connect a compressed air supply to the closer air
inlet (G). Actuate the cylinder with approximately
50 psi (0.35 MPa, 3.5 bar) air pressure to retract
the closer rod and keep the closer springs com-
pressed.
WARNING
MOVING PARTS HAZARD
The valve air cylinder is spring–loaded
and parts may fly out or spring apart
when the valve is disassembled and
cause serious injury. During service
procedures that will expose internal meter parts,
wear protective eyewear and keep the closer
spring compressed, as instructed in step 6.
7. Disconnect the pressure sensor cable (K) from the
connector (L).
8. Remove the guard (39).
9. Slide the rubber boot (34) back to expose the two
set screws (35).
10. Disconnect the fluid needle (29) from the connec-
tor (37) by unscrewing the two set screws (35).
Fig. 3
TI1393A
40
39
21
35
37
1
3
2
Part No. 233678 Shown
J
G
K
Lubricate all o–rings and seals
with lithium–based grease prior to
installation.
Do not service the motor. Contact
a Graco distributor for service.
Torque to 32 in-lb (3.6 NSm).
24
B
23
26
27
28
29
22
1
A
33 1
36
26
31
30 1
32
34
1
2
3

8 309384
Service
11. Remove the screws (24), and separate the fluid
section from the fluid head mount (21).
12. Remove the rubber boot (34).
13. Separate the fluid body (22) and adapter (23).
14. Remove the seat (27) and fluid needle (29).
15. Unscrew the seal housing (32).
16. Remove the seals (30 and 33), o–ring (26), washer
(36), and bushing (31).
17. Clean the parts in a non–flammable cleaning fluid
that is recommended by your material supplier.
Replace parts as needed.
NOTE: Use lithium–based grease to lubricate o–rings
and seals.
18. Lubricate seal (orange) (33) and press the seal
into the fluid body (22), with the lips of the seal
facing into the fluid body.
19. Install the washer (36) on top of seal (33).
20. Lubricate seal (black) (30) and press into the
bushing (31), with the lips of the seal facing into
the bushing.
21. Install the o–ring (26) on the end of the bushing
(31).
22. Install the bushing (31) into the fluid body (22),
with the o–rings facing into the fluid body.
23. Screw seal housing (32) into fluid body (22).
24. Lubricate the fluid needle shaft (29). Turn the
needle as you install the shaft through the fluid
body (22), seals (30 and 33), and bushing (31).
25. Install the o–rings (26 and 28) and lubricate them.
26. Press and turn the seat (27) into the fluid body
(22).
27. Replace rubber boot (34) over the connector (37)
and secure end to the motor face plate. Slide boot
back to expose set screw holes.
28. Press the fluid body (22) and adapter (23) together
and secure them with the four screws (24) and
split lock washers (25). Torque the screws to 32
in-lb (3.6 NSm).
29. Slowly relieve the air pressure from the metering
valve to release the closer.
CAUTION
The motor shaft is forced to the full forward position
by the closer. Slowly relieve the air pressure to
prevent excessive impact of the shaft, which could
damage the equipment.
30. Finger–tighten one set screw (35) on the connec-
tor (37). Tighten the second set screw and torque
to 15 in-lb (1.7 NSm). Retighten the first set screw
and torque to 15 in-lb (1.7 NSm).
31. Slide the rubber boot (34) back to cover the set
screws (35), making sure the end is still secured
over the motor face plate.
32. Install the guard (39).
33. Connect the pressure sensor cable (K) to the
connector (L).
34. Mount the metering valve.
35. Connect the fluid lines to the metering valve fluid
line inlet (A) and (B).
36. Connect the closer air line to the closer air inlet
(G).
37. Turn on the fluid supply.
38. Recalibrate the PrecisionFlo system. See the
PrecisionFlo control manual.

309384 9
Service
Closer Service
WARNING
SKIN INJECTION HAZARD
To reduce the risk of a serious injury,
including an injection injury, follow the
Pressure Relief Procedure on page 5
before checking or servicing the equipment and
whenever you are instructed to relieve the pres-
sure.
1. Relieve the pressure in the system.
2. Disconnect the electrical cable (C) from the Meter-
ing Valve connector (E). See Fig. 2, page 4.
3. Disconnect the fluid lines from the metering valve
fluid inlet (A) and outlet (B).
4. Disconnect the closer air line from the closer air
inlet (G). See Fig. 4.
5. Unmount the Metering Valve and take it to a clean
work area with a compressed air supply.
6. Connect a compressed air supply to the closer air
inlet (G). Actuate the cylinder with about 50 psi
(3500 kPa, 3.5 bar) air pressure to retract the
closer rod and keep the closer spring compressed.
WARNING
MOVING PARTS HAZARD
The valve air cylinder is spring-loaded
and parts may fly out or spring apart
when the valve is disassembled and
cause serious injury. During service procedures
that will expose internal meter parts, wear protec-
tive eyewear and keep the closer spring com-
pressed, as instructed in step 6.
7. Remove the eight screws (3) from the closer
assembly (2), and remove the closer assembly.
See Fig. 4.
8. Slowly relieve the air pressure from the Metering
Valve to release the closer.
9. Disconnect the air line from the closer air inlet (G).
10. Press down on the cylinder body cover to prevent
the parts from springing apart, and remove the
screws (107) from the closer cover. See Fig.6.
11. Remove the cylinder cap (111) from the cylinder
(108).
12. Remove the o-rings (103) from the cover (104).
WARNING
MOVING PARTS HAZARD
The rod extension (102) and spring cup
(112) may fly apart as the rod extension
is unscrewed from the cylinder rod (R),
due to the pressure from the spring (113). Wear
eye protection to reduce the risk of serious injury
from moving parts.
Fig. 4
2
G
TI1392A
3
Fig. 5
110
102
TI1392A
107

10 309384
Service
Closer Service (continued)
13. Remove the spring (109) from the cylinder body
(108). See Fig. 6.
14. Remove the rubber bumpers (101) from the cylin-
der cap (111) and valve rod (102).
15. Inspect the parts for damage and clean or replace
them as needed. Lubricate the o-rings with lithium-
based grease before re-installing them.
16. Install the o-ring (114) in the cylinder body over the
piston (113). Insert the piston and the spring (109)
into the cylinder body (108).
17. Apply anaerobic sealant (Loctiter242 or 243 or
equivalent) to the threads of the four screws (107).
18. Compress the spring enough to engage the screw
threads into the closer cover. Torque the four
screws (107) to 24–30 in-lb (2.7–3.4 NSm).
19. Install the cover o-rings (103).
20. Install the rubber bumpers (101) on the end of the
rod closer (102) and the cylinder cap (111).
21. Connect a compressed air supply to the closer air
inlet (G). Actuate the cylinder to retract the closer
rod and keep the closer spring compressed.
22. Secure the closer assembly to the metering valve
with the eight screws (3). See Fig. 4.
23. Slowly relieve the air pressure from the Metering
Valve to release the closer.
CAUTION
The motor shaft is forced to the full forward position
by the closer. Slowly relieve the air pressure to
prevent excessive impact of the shaft, which could
damage the equipment.
24. Disconnect the air line from the closer air inlet (G).
Fig. 6 TI1392A
107
109
110
114
108
105
104
111
103
113
112
102
101
112
115
101