Dover Wilden Original A8, Инженерия, эксплуатация и обслуживание

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WILDEN PUMP & ENGINEERING, LLC WIL-10270-E-02
SECTION 8B
AIR VALVE / CENTER BLOCK
DISASSEMBLY
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 follow-
ing procedure will ensure that the air valve on your Wilden
pump will provide long trouble-free service.
AIR VALVE BODY AND PISTON
ASSEMBLY AND DISASSEMBLY:
The air valve body and piston can be disconnected from the
pump by removing the four socket head cap screws which
attach it to the center block. The piston in the air valve is
aluminum with a dark gray anodized coating. The piston
should move freely and the ports in the piston should line up
with the ports on the face of the air valve body (see below).
The piston should also appear to be a dull, dark gray in color.
If the piston appears to be a shiny aluminum color, the air
valve is probably worn beyond working tolerance and should
be replaced.
If the piston does not move freely in the air valve, the entire
air valve should be immersed in a cleaning solution.
[NOTE: Do not force the piston by inserting a metal object.]
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. If the air
valve piston does not move freely after the above cleaning,
the air valve should be disassembled as follows: remove the
snap ring from the top end of the air valve cylinder and apply
an air jet to the 3/16-inch hole on the opposite end of the
air valve face. (See Figure C.) CAUTION: The air valve end
cap may come out with considerable force. Hand protection
such as a padded glove or rag should be used to capture
the end cap.