A I R V A L V E / C E N T E R S E C T I O N D I S A S S E M B L Y
Small nicks can usually be dressed out and the piston
returned to service. Make sure that the guide pin is
straight and smooth or the piston will not move freely in
the cylinder. Clean out anti-centering pin holes located
at each side of the piston. Pin holes are located on each
side of the annular groove on the top of the piston and
travel to each end. New o-rings should be installed on
the end caps. Lubricate the o-rings and install the end
caps, assuring that proper alignment of the piston and
cylinder ports are maintained (see fi gure A, previous
page). Reinstall air valve to center block of pump.
Glyd™ Ring Replacement:
When the Glyd™ rings become worn, they will no longer
seal and must be replaced.
Center Block Assembly:
The pump’s center block consists of a die cast housing
with a cast-in bronze bushing (see fi gure C). The bushing
has eleven grooves cut on the inside diameter. There are
seven Glyd™ rings that fi t into these grooves (see fi gure
D). 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. When bushing wear becomes
excessive, a new center block must be used.
P/N 08-3806-09
P/N 15-3210-55-225
Grooves in
bushing which
contain Glyd™ rings
3/16" DRILL
BLEED-OFF
PORT
3/16" DRILL
BLEED-OFF
PORT
5/32" DRILL
BLEED-OFF
PORT
Figure C
(Side View)
Figure E
Center Block (Front View)
Figure D
WILDEN PUMP & ENGINEERING, LLC
16
WIL-11140-E-03
