that it does not push the center tube over to one side.
c. Remove the dirty wastex and the center screen
Check the packing frequently during packing by trying
covered tube. These can be slipped straight up off the
the upper steel washer on the center tube.
inner center tube.
f. Replace top washer and retaining wire and
d. Remove the dirty wastex from the screen
install element in filter housing.
covered tube being careful not to damage the screen.
g. Replace top casting and gasket. Check gasket
e. Wash screen covered tube and replace in
and if it is not in good condition replace with new one.
element. Repack element with wastex. Pack evenly
Tighten the four nuts on the top evenly. Start engine
and firmly to eliminate voids through the filtering
and check cover for leaks.
material. Use a blunt-end stick to pack wastex down
firmly. It must be packed evenly around center tube so
Section XV. COMPRESSOR GOVERNOR
tension of the regulating spring (35) will then move the
110. Governor Details
cutout valve to its seat.
a. This governor is of the pneumatic double safety
valve type and consists of two distinct positions; the
c. After cutout valve (38) has been returned to its
operating portion and the pipe bracket.
Pipe
seat, the main reservoir pressure will continue to be
connections to the compressor and to tile main reservoir
supplied to the compressor unloading device through
are provided for in the pipe bracket so that I lie
passages a, q and c, past tail valve (43), and through
operating portion may be removed for repairs or
port g to the unloading device. The unloading device
replacement without breaking any pipe joints.
remains in the cutout position, allowing the compressor
to run without load, until the main reservoir pressure is
reduced to a point where the force exerted by it against
with the compressor in operation and main reservoir
the face of the cut-in valve (39) is equal to a fraction
pressure building up, main reservoir pressure is
below the tension of the regulating spring (35).
delivered to the face of the cutout valve (38), also to
underside of the tail valve (43) of the cut-in valve (39),
112. Cutting-in Operation
via the main reservoir pipe connection, passage r,
chamber A, through strainer (49) to passages a and q.
a. When the force of the main reservoir pressure,
which is acting upon the full face area of the cut-in valve
(39), is reduced to a fraction below the tension of the
111. Cutting-Out Operation
regulating spring (35), cut-ill valve (39) will be moved to
a. The main reservoir pressure building up against
its normal cut-ill position, seating the tail valve (43)
the face of cutout valve (38) eventually becomes
against the tension of its spring (45), closing
sufficiently high to overcome the tension of the cutout
communication between the mail reservoir and the
valve regulating spring (35), causing valve (38) to lift
compressor unloading device and, in turn, opening
from its seat and, due to the construction of this valve,
communication between the unloading device and the
the slight lifting from seat exposes an increased area,
atmosphere, through passage g, port j, through passage
causing the valve to lift quickly, at the same instant
d to Ex.
delivering pressure via port e to the face of the cut-in
valve (39). The main reservoir pressure now acting
b. Communication is also opened between the
upon the full area of valve (39) will overcome the
cutout regulating spring chamber F and the atmosphere,
tension of its regulating spring (35), causing the valve
through passages f and in, port j, cut-in regulating spring
(39) to lift with a snap, forming a seal at its upper seat
chamber D, and passage d to Ex, thereby freeing spring
which will close communication from the compressor
chamber F of-main reservoir pressure. The cutout
unloading device to the atmosphere (through ports g
valve (38) which is now held to its seat only by the
and d) and, at the same time, connect main reservoir
tension of the regulating spring (35), will immediately
pressure to the compressor unloading device through
rise from its seat upon a slight increase of main
port g.
reservoir pressure above the setting of the regulating
spring.
b. At the same time, main reservoir pressure will
be connected to the cutout regulating spring chamber F
through port f, resulting in equalizing the air pressures
on each side of cutout valve (38), whereupon the
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