BENDIX AD-9 AIR DRYER User Manual

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CONTROL
PORT
SUPPLY
PORT
SD-08-2412
Bendix
®
 AD-9
 Air Dryer
EXTENDED PURGE AD-9
 AIR DRYER
STANDARD AD-9
 AIR DRYER
OUTER
SHELL
WIRING HARNESS
CONNECTION
DELIVERY PORT
DESCRIPTION
The function of the AD-9
 air dryer is to collect and remove
air system contaminants in solid, liquid and vapor form before
they enter the brake system. It provides clean, dry air to the
components of the brake system which increases the life of
the system and reduces maintenance costs. Daily manual
draining of the reservoirs is eliminated.
The AD-9
 air dryer consists of a desiccant cartridge and a
die cast aluminum end cover secured to a cylindrical steel
outer shell with eight cap screws and nuts. The end cover
contains a check valve assembly, a safety valve, three
threaded air connections and the purge valve housing
assembly. The removable purge valve housing assembly
incorporates a purge valve mechanism and a turbo charger
cut-off feature that is designed to prevent loss of engine
“turbo” boost pressure during the purge cycle of the AD-9
air dryer. For ease of serviceability, the desiccant cartridge
and discharge check valve assembly are screw in type. The
purge valve housing assembly, which includes the heater
and thermostat assembly, and the discharge check valve
assembly, is serviceable from the exterior of the air dryer,
while servicing the screw-in desiccant cartridge requires
removal of the air dryer assembly from the vehicle.
The AD-9
 air dryer has three female pipe thread air
connections and each is identified as follows:
  Port l.D.
Function/Connection
  CON 4 ............... Control Port
(purge valve control and turbo cut-off).
  SUP 11 ............. Supply Port (air in).
  DEL 2 ............... Delivery Port (air out).
OUTER
SHELL
SUPPLY
PORT
WIRING HARNESS
CONNECTION
DELIVERY PORT
CHECK
VALVE
ASSEMBLY
END COVER
CHECK
VALVE
ASSEMBLY
END COVER
CONTROL
PORT
FIGURE 1  - AD-9
 AIR DRYER MODELS