Sunrise Medical DeVilbiss 505DZ Service Manual page 45

C O M P O N E N T T E S T I N G , R E P A I R & R E P L A C E M E N T
To clean the four-way valve (Figure 42):
1. Remove the two allen head valve retaining screws from the top of the four-way valve.The top of the valve body can now be
removed along with the pilot valve.The valve manifold will remain on the unit. A rubber gasket located between the valve body
and manifold should also be removed.
2. Remove the end cap screws from both ends of the valve so that the end plates, plastic spacers, and spring can be removed. Note
the position of these parts.
3. Carefully remove spool from valve body. (NOTE—Spool and sleeve are a matched set. Care should be taken not to mix
different valve parts.)
4. Using a non-metallic rod or dowel with a diameter no greater than the sleeve, slowly push the sleeve out either end of the valve
body. (NOTE—Pushing too fast will cause o-rings to roll and jam.) Inspect the o-rings on sleeve. If they are badly worn or
defective, they should be replaced using the Valve Rebuild Kit (part #MC44I-707).
5. The spool and sleeve can be cleaned using a spray-on evaporative electro-contact cleaner; e.g. ENVI•RO•TECH™ 1677, or
cleaned with a detergent powder; e.g. ALCONOX®. If using these cleaners, follow manufacturer's instructions carefully. DO
NOT USE ANY TYPE OF CLEANSER THAT IS ABRASIVE OR LEAVES A RESIDUE.
6. Rinse the spool and sleeve thoroughly and dry with a soft, clean, lint-free cloth.
7. Ensure that the air passages (ports) in both the valve body and manifold are free of any foreign matter. A clean, lint-free cloth or
a compressed air hose can be used to clean these.
8. Carefully push sleeve into valve body (turning it slightly) so you do not cut or nick the o-rings.To ensure proper placement of
sleeve, use the spring retaining spacer and push the sleeve and spacer in until the spacer is flush with the end cap mounting
surface.
9. Reassemble remaining parts of valve in reverse order.
Valve retaining screws
*Spring
*Spring retaining spacer
*End gasket
End cap
*Included in the four-way valve rebuild kit (part# MC441-707)
To replace four-way valve:
1. Align valve body and gasket on manifold. Ensure that gasket is aligned properly. Secure with two allen head screws.
2. Attach pilot pressure tubing to pilot valve.
3. Reconnect the two wires on terminals of pilot valve.
4. Replace cabinet and secure with fasteners.
*Sleeve O-ring
Valve body
*Base gasket
45
*O-ring
*Spacer
*Spool
ALCONOX ®
ENVI•RO•TECH™1677 is a trademark of Tech Spray, Inc.
End cap screws
End cap
Pilot valve
Figure 42
is a registered trademark of Alconox, Inc.