8
3.
Do not attempt to install, remove, disassemble or
assemble a component until you have read and
thoroughly understand the recommended
procedures. Use only the proper tools and observe
all precautions pertaining to use of those tools.
4.
If the work is being performed on the vehicle’s air
brake system, or any auxiliary pressurized air
systems, make certain to drain the air pressure from
all reservoirs before beginning ANY work on the
vehicle. If the vehicle is equipped with an AD-IS
™
air dryer system or a dryer reservoir module, be
sure to drain the purge reservoir.
5.
Following the vehicle manufacturer’s
recommended procedures, deactivate the electrical
system in a manner that safely removes all
electrical power from the vehicle.
6.
Never exceed manufacturer’s recommended
pressures.
7.
Never connect or disconnect a hose or line
containing pressure; it may whip. Never remove a
component or plug unless you are certain all
system pressure has been depleted.
8.
Use only genuine Bendix
®
replacement parts,
components and kits. Replacement hardware,
tubing, hose, fittings, etc. must be of equivalent
size, type and strength as original equipment and
be designed specifically for such applications and
systems.
9.
Components with stripped threads or damaged
parts should be replaced rather than repaired. Do
not attempt repairs requiring machining or welding
unless specifically stated and approved by the
vehicle and component manufacturer.
10. Prior to returning the vehicle to service, make
certain all components and systems are restored to
their proper operating condition.
11. For vehicles with Antilock Traction Control (ATC),
the ATC function must be disabled (ATC indicator
lamp should be ON) prior to performing any vehicle
maintenance where one or more wheels on a
drive axle are lifted off the ground and moving.
AD-4
™
AIR DRYER REMOVAL
1. Park the vehicle on a level surface and prevent movement
by means other than the brakes.
2. Drain all reservoirs to 0 p.s.i. (0 kPa).— Caution:
Compressor discharge line may still contain residual
pressure.
3. Identify and disconnect the three air lines from the end
cover and note the position of end cover ports relative to
the vehicle.
4. Pull boot from the thermostat and heater cover and slide
it onto the wire to expose the connection. Remove nut
and disconnect electrical wire from the terminal. Note:
Vehicles with insulated ground (2 wire) system will have
two boots and two terminals to be disconnected. (See
Figures 5 & 8.)
5. Loosen the 5/16" X 4-1/2" hex bolt securing the upper
and lower mounting straps. Disengage the mounting
END
COVER
SPECIAL
WASHER
LOCK NUT
LOWER RIGHT ANGLE
BRACKET
EXTRA
LONG
CAP SCREW
bracket hook from the end cover (Refer to Figure 6.)
Note: If the AD-4
™
air dryer being serviced has a right
angle bracket instead of a lower mounting strap and
safety hook, proceed to step 6, otherwise proceed to
step 7.
6. Remove, retain and mark the two 3/8" end cover cap
screws, lock nuts and four special washers that retain
the lower mounting bracket to the end cover, also mark
these two holes of the end cover. (These bolts are longer
than the other 6 bolts.)
7. Remove the AD-4
™
air dryer from its mounting brackets
on the vehicle.
DISASSEMBLY
The following disassembly and assembly procedure is
presented for reference purposes and presupposes that a
major rebuild of the AD-4
™
air dryer is being undertaken.
Several replacement parts and maintenance kits are available
which do not require full disassembly. The instructions
provided with these parts and kits should be followed in lieu
of the instructions presented here. Refer to Figure 6 during
disassembly.
Caution: While performing service on the AD-4
™
air
dryer, it is not recommended that a clamping device
(vise, C-clamp, etc.) be used to hold any die cast
aluminum component as damage may result. To hold
the end cover, install a pipe nipple in the supply port
and clamp the nipple into a vise.
1. Remove the remaining 3/8" lock nuts, special washers
and cap screws from the flange of the air dryer and
separate the end cover from the air dryer outer housing.
Separate the desiccant cartridge and sealing plate from
FIGURE 7 - LOWER BRACKET INSTALLATION
