Bendix Commercial Vehicle Systems AD-1 AND AD-2 AIR DRYERS 7/04 - Manual (Page 7)

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FIGURE 7 - REPLACEMENT DESICCANT CARTRIDGE
FIGURE 6 - DESICCANT SEALING PLATE
End Cover Removal
1.
Loosen the three cap screws on the end cover and turn
the retaining clamps aside (cap screws may be left
finger tight).
2. Locate the notch in the air dryer shell. While pushing the
end cover up into the dryer, insert the blade of a
screwdriver in the notch and slowly pry out the retaining
ring. If the cartridge bolt has loosened the cartridge
spring may exert a force on the end cover retaining ring
making removal of the retaining ring and end cover
difficult. This spring force will prohibit the end cover
moving up into the dryer shell when pushed up. Warning:
This same force can also cause the end cover to come
out of the air dryer shell unexpectedly during the removal
process. Exercise extreme caution to prevent bodily
injury.
3. Do not stand or lay directly under the end cover while
servicing. Assure adequate clearance between the end
cover and other surfaces to prevent hand injury if the end
cover dislodges rapidly during removal. NOTE: BE
CERTAIN THE DESICCANT SEALING PLATE
ASSEMBLY COMES OUT WITH THE CARTRIDGE.
CAUTION: Before attempting to remove the desiccant
sealing plate, measure the cartridge bolt from
the top of the desiccant plate lock nut to the
end of the bolt threads. If that measurement is
approximately 3-3/16 inches, proceed with the
disassembly.
If the bolt measures approximately 1-9/16
inches, disassemble using CAUTION.
Approximately 75 pounds of spring force will
remain against the desiccant plate when the lock
nut reaches the end of the bolt thread and is
removed.
REMOVING AND REBUILDING THE AD-1 ™ AND
AD-2 ™ AIR DRYER DESICCANT SEALING PLATE
Before the desiccant cartridge can be replaced or rebuilt
the desiccant sealing plate must be removed. It is
recommended that all non-metallic parts be replaced when
the plate is removed. In the past, three methods have been
employed, to secure the desiccant sealing plate to the
desiccant cartridge: a Tru Arc retaining ring, two special
thin nuts, and the latest method, a single hex lock nut.
Removing the securing device will permit the desiccant plate
to be separated from the desiccant cartridge. After removing
the desiccant cartridge:
1. Remove the two o-rings from the desiccant plate and
discard them.
2. Remove the ball check valve retaining clip and remove
and discard the rubber ball valve.
3. Clean the desiccant plate thoroughly using a quality
commercial solvent, making sure the purge orifice and
check valve seat are clean.
4. Install a new ball check valve and replace the retaining
clip and screw (Figure 5).
5. Thoroughly lubricate the two new o-rings and install them
in their respective grooves in the purge plate (Figure 6).
6. Set the desiccant sealing plate aside for reinstallation
on the desiccant cartridge.