Nordson EFD 782RA Manual

782RA Spray Valve
MAINTENANCE & PARTS GUIDE
IMPORTANT!
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contact EFD or go to www.efd-inc.com/contact
EFD, Inc.
East Providence, RI USA
800-556-3484; [phone] (outside the USA)
[email protected] www.efd-inc.com
EFD International Inc.
Dunstable, Bedfordshire, UK
0800 585733 or [phone]
Ireland 00800 8272 9444
[email protected] www.efd-inc.com
EFD, Inc., Asia
China: [phone]
[email protected] www.efd-inc.com/cn
Singapore: [phone] [email protected]
®
A NORDSON COMPANY

Motor mount / gear shroud
#7863
Pinion gear
#7862
Nozzle
extension
#7841-3
Nozzle #7841
Spur gear
retainer
#7847
Rotor
bearing,
large
#7844B
Rotor
#7842-3
Rotor
bearing,
small
#7844A
Gear cover
#7864
Screw #H2-56X1/4PH
Nut #7842A
Bearing seal #7852
Spur gear #7845 Screw
#H2-56X1/4FH
42
3
Valve maintenance
To thoroughly clean the fluid body and
replace needle packings:
1. Remove needle stroke control knob
and spring.
2. Remove the gear cover.
3. Remove the rotor retainer nut, then
the rotor, nozzle, fittings and motor
from the fluid body.
4. Remove the motor mount and
motor assembly.
5. Remove the fluid body from the air
cylinder body. Remove the O-ring
from the fluid body.
6. Clean the fluid body, rotor and noz-
zle in appropriate solvent.
Note: Rotor bearings can be soaked in
light oil for one hour to penetrate past
the seals. Replace bearings if rotor does
not rotate smoothly.
7. Use tool #7803 to remove needle
packings from fluid body.
8. Remove any remaining packings
and the spring from the needle.
Note: The lower cylinder needle O-ring
is held in place by a flat retaining washer
that also serves as the packing-spring
seat. The washer may come out with
the spring. Ensure that it is back in place
before reinstalling the packing spring.
9. Clean the needle with a cloth
dampened in solvent.
Valve Disassembly
and Reassembly Procedures
www.efd-inc.com [email protected] USA 800-556-3484 Europe [phone] Asia [phone]
Sales and service of EFD dispensing systems are available worldwide.

Needle
stroke
control
#780SR-KIT
Thrust
washer
#7809
Thrust
washer
#7809
Piston
return
spring
#7802
O-ring #7519
Piston and needle
assembly #7805-SS-3
Air inlet fitting #78518M
O-ring
#7806 Air motor
assembly
#7860 Air inlet fitting #78518M
Fluid body #7875
Fluid inlet fitting #7543BP
O-ring
#7517
Needle packing assembly #7810
Retaining washer #7807
Air cylinder body #7811
Snap ring
#7526
Packing spring #7808
1
5
7
10
11
13
14
15
17
16
10. Lubricate the needle with Nye
Lubricant #865. Reinstall the
needle packing spring and a new
packing kit.
11. Install a new O-ring (#7517) on the
fluid body.
12. Reassemble valve in reverse order.
Replacing piston and needle
assembly or piston O-ring:
13. Remove needle stroke-control
knob.
14. Remove piston return spring and
thrust washers.
15. Remove the snap ring.
16. With small pliers on the spring
pilot, pull the piston and needle
assembly out of air cylinder. The
piston and needle assembly is one
unit and cannot be disassembled.
17. Clean air cylinder body wall and
lubricate with Nye Lubricant #865.
18. Reassemble the valve in reverse
order.
General Maintenance Kit
#780S-RK
Includes O-rings, needle-packing
assembly and lubricant.
Maintenance Tools:
6” adjustable wrench
5/16” open-end wrench
snap-ring pliers
packing extraction tool #7803
www.efd-inc.com [email protected] USA 800-556-3484 Europe [phone] Asia [phone]
Sales and service of EFD dispensing systems are available worldwide.

Troubleshooting Guide
No fluid flow
•If valve operating air pressure is too low,
the valve will not open. Increase air
pressure to 70 psi (4.8 bar) minimum.
•The reservoir air pressure may not be
high enough. Increase pressure.
•The nozzle may be clogged. Clean
the nozzle.
•The stroke adjustment control may
be closed. If it is closed, open coun-
terclockwise one turn.
•The control and the atomizing air
lines may be reversed. Check for
proper connection.
Valve does not provide clean shut-off,
leaving a build-up on the nozzle
•Atomizing air pressure may be too
low. Increase the air pressure.
•Atomizing air delay setting may be too
low. Increase air delay setting.
Fluid continuously drips from the
nozzle after the valve shuts off
•A continuous drip can be caused by
improper seating of the needle in the
nozzle seat. Remove the nozzle,
clean the needle and nozzle, and
replace worn or damaged parts.
•If the fluid body has not been fully
turned onto the air cylinder body
during reassembly, the needle will not
seat in the nozzle. Check fluid body
installation.
•Needle packings may be binding due
to leakage, preventing the needle
from fully closing. Disassemble the
valve and replace the packings if
there is evidence of leakage.
Fluid flows from the nozzle but will not
spray
•Atomizing air pressure may be too
low. Increase air pressure.
•If the fluid viscosity is too high, it will
not atomize. Reduce viscosity.
•Check atomizing hose connection
“B” at the controller.
A NORDSON COMPANY
USA: 800-556-3484 or [phone]
Europe: 0800 585733 or [phone]
Asia: [phone]
[email protected] www.efd-inc.com
©2006 Nordson Corporation 782-MAINT-01 v062606