WIL-10252-E-01
Wilden
®
18
Disassembly / Reassembly
The air valve assembly consists of both the air valve body and piston
and the center block. The unique design of the air valve relies only on
differential pressure to effect the diaphragm shift. It is reliable and
simple to maintain. The bushing in the center block, along with the
diaphragm shaft, provides the “trigger” to tell the air valve to shift. The
following procedure will ensure that the air valve on your Wilden pump
will provide long trouble-free service.
GLYD™ RING REPLACEMENT:
When the Glyd™ rings become worn, they will no longer seal and must
be replaced. Due to the design characteristics of the Glyd™ rings, it is
suggested that you use the Ringer Seal installation kit when replacing
Glyd™ rings. Consult EOM- Ringer for installation instructions.
CENTER BLOCK ASSEMBLY:
The pump’s center block consists of a die cast housing with a cast-in-
bronze bushing (Figure G). Figure H shows T4 injection-molded
polypropylene center section and alignment with air valve. The
bushing has eleven grooves cut on the inside diameter. There are
seven Glyd™ rings that fit in these grooves (see Figure E). Since
these Glyd™ rings form a part of the shifting function of the pump, it
is necessary that they be located in the proper grooves. The bronze
bushing is replaceable in cast iron center block only. When bushing
wear becomes excessive, a new center block must be used.
This soaking should remove any accumulation of sludge and grit
which is preventing the air valve piston from moving freely. Also,
remove and clean the air valve screen.
Figure F
(Side View)
AIR FILTER
SCREEN
DRILL
ALIGNMENT
AIR INLET
AIR VALVE
PISTON
CENTER BLOCK
Figure E
Figure H
DRILL
ALIGNMENT
Figure G
Center Block
(Front View)
END CAP
P/N 15-3800-09-07
P/N 15-3800-09-07
Grooves In Bushing Which Contain Glyd™ Rings
*Refer to Section 8 for torque specifications.
