EFD 781S MAINTENANCE GUIDE

781S Series Dispense Valve

MAINTENANCE & PARTS GUIDE

Electronic pdf files of EFD® manuals are also available at

www.efd-inc.com/manuals.html.

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®

A NORDSON COMPANY

For EFD sales and service in over 30 countries, contact EFD or go to www.efd-inc.com/contact

EFD, Inc.

East Providence, RI USA

800-556-3484; [phone] (outside the USA) [e-mail] www.efd-inc.com

EFD International Inc.

Dunstable, Bedfordshire, UK

0800 585733 or [phone] Ireland 00800 8272 9444 [e-mail] www.efd-inc.com

EFD, Inc., Asia

China: [phone]

[e-mail] www.efd-inc.com/cn Singapore: [phone] [e-mail]

Valve Disassembly and

Reassembly Procedures

CAUTION: To prevent damage, the valve must be disassembled starting at the fluid outlet end of the valve.

Valve maintenance

To thoroughly clean the fluid body and replace needle packings:

1.Remove needle stroke control knob and spring.

2.Remove air cap retainer, then air cap, nozzle and fittings.

3.Remove fluid body from air cylinder body using a .11” hex wrench, then remove O-ring.

4.Clean fluid body, air cap and nozzle in appropriate solvent.

5.Use extraction tool #7803 to remove needle packings from fluid body.

6.Remove any remaining packings and spring from needle.

Note: Before reassembling, clean fluid body, air cap and nozzle in appropriate solvent and replace O-ring. Clean needle with cloth dampened in solvent.

Reassemble the valve in reverse order of disassembly. Ensure that the small O-ring and washer on the bottom of the air cylinder body are back in place before reinstalling the packing spring. Lubricate parts indicated with Nye Lubricant #865 included in the Maintenance Kit.

	2	Fluid inlet fitting
		#7543BP
	Nozzle air	#7610BP

	cap retainer	Screws
	#7819SS
		H6-
	(stainless steel)

3 #7825

5

Air cylinder body #7879-SS steel)

aluminum)

Packing

11

Nozzle/air cap Round #7857-46SS #7857-28SS #7857-14SS #7857-46WA-SS

4

Fan #7857F-46SS #7857F-28SS #7857F-14SS #7857-46WF-SS

O-	Retaining	O-ring (Buna-N)
#4049	washer #7807	#7806
Fluid body
#7878-SS (stainless steel)
#7878 (hard-coated aluminum)

www.efd-inc.com [e-mail] USA 800-556-3484 Europe [phone] Asia [phone] Sales and service of EFD dispensing systems are available worldwide.