MicroCoat MC800 Series System
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www.nordsonefd.com [email protected]
800-556-3484 Sales and service of Nordson EFD dispensing systems are available worldwide.
Spray Valve Maintenance
Before performing any maintenance, set the System Pressure Switch to the Off position and depressurize the tank
reservoir by lifting the lever on the tank pressure relief valve.
WARNING
When using filtered plant air and clean lubricants, the MC785M series spray valves are designed for long-term
performance without scheduled maintenance.
If lubricant flow stops or becomes erratic, first review “Troubleshooting” on page 31. Cleaning the nozzle will solve
most problems related to lubricant flow and spray patterns.
To Clean the Nozzle
Remove the air cap retainer nut, air cap and nozzle from the outlet end of the valve. Clean and reinstall.
Valve Disassembly
NOTE:
Refer to the diagram on page 28.
1. Remove air cap retainer nut, air cap and nozzle from the outlet end
of valve.
2. Remove diaphragm chamber cap, diaphragm return spring and
needle / diaphragm assembly from the valve body.
3. Remove diaphragm retaining nut and spring locating washer from
the needle, then remove and discard old diaphragm.
NOTE:
Install a new diaphragm (#7021727) each time the valve is
reassembled.
4. Clean all parts in mineral spirits.
Valve Reassembly
NOTE:
Refer to the diagram on page 28.
1. Place the new diaphragm over the threaded end of the needle. The black Viton side of the diaphragm should
face the threaded end. The blue-grey Teflon side should face the wetted side of the valve.
2. Place the spring locating washer over threaded end of the needle. The stepped side should face the threaded
end.
3. Install a new diaphragm retaining nut (included with #7021727 diaphragm) and turn it until the nut starts to feel
tight and the diaphragm cannot be rotated on the needle with fingers. Avoid crushing the diaphragm causing it
to bulge away from the washer.
4. Install the needle / diaphragm assembly into the valve body, then install diaphragm return spring and diaphragm
chamber cap, and tighten firmly.
5. Reinstall the nozzle, air cap and air cap retainer.
The air cap retainer nut should be tightened with a wrench to prevent loosening due to press vibration
Maintenance Tools
8" adjustable wrench
7/8" open end wrench
5/16" box end wrench
1/4" nut driver
