BENDIX AD-9 Service Data

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AD-9 AIR DRYER
END COVER
CHECK
VALVE
DELIVERY PORT
ASSEMBLY
EXTENDED PURGE AD-9 AIR DRYER
FIGURE 1 - AD-9 AIR DRYER MODELS
DESCRIPTION
The function of the AD-9 Air Dryer is to collect and remove
air system contaminants in solid, liquid and vapor form be-
fore 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
UPPER
BRACKET
OUTER
SHELL
LOWER
BRACKET
PORT
CONTROL
SUPPLY
PORT
WIRING HARNESS
CONNECTION
END COVER
CHECK
VALVE
ASSEMBLY
DELIVERY PORT
STANDARD AD-9 AIR DRYER
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 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).
UPPER
BRACKET
LOWER
BRACKET
CONTROL
WIRING HARNESS
CONNECTION
OUTER
SHELL
PORT
SUPPLY
PORT
1