12
VEHICLE PREPARATION
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).
LOCATING AD-4
™
AIR DRYER ON VEHICLE
1. The AD-4
™
air dryer must be mounted vertically (purge
exhaust toward road surface) outside the engine
compartment in an area of air flow while the vehicle is in
motion. The AD-4
™
air dryer must not be exposed to
direct wheel splash (located behind axle mud flap is
acceptable).
2. Locate the AD-4
™
air dryer as close to the first (supply)
reservoir as possible.
3. Do not locate the AD-4
™
air dryer near heat producing
components such as the vehicle exhaust and make
certain adequate clearance from moving components
(e.g. drive shaft, suspension, pitman arm, etc.) is
provided.
4. Locate the AD-4
™
air dryer on vehicle so that a minimum
of 11 inches (28 cm) clearance below the end cover is
available to allow servicing. Alternatively, provide access
to the bracket bolts so the unit may be removed for
servicing.
5. When choosing the mounting location for the AD-4
™
air
dryer, note the discharge line length requirements stated
under the heading Connecting the Air Lines, elsewhere
in this instruction sheet.
Important Note: Under normal operating conditions, the
maximum inlet air temperature for the AD-4
™
air dryer is
160 degrees Fahrenheit.
MOUNTING THE AD-4
™
AIR DRYER
1. Assemble the mounting strap and mounting bracket as
illustrated in Figures 5 & 6 using the 5/16" screws, nuts
and lock washers. Make certain the mounting bracket
hook is installed on the 5/16" screw of the lower mounting
bracket and that it engages the AD-4
™
air dryer end cover.
Make certain that the inside surface of the top mounting
strap bears entirely on the cylindrical surface of the dryer
shell and that it does not overlap the domed top. The
brackets should be a minimum of 5.5 inches apart. After
positioning the mounting straps according to the
installation requirements, torque both 5/16" screws to
80-120 inch pounds.
Note: The mounting bracket at the base of the AD-4
™
air
dryer can be of two types. The one described above or a
single piece right angle bracket. (See Figure 7.) To install
the single piece lower mounting bracket, remove and
discard two of the bolts and nuts that retain the end
cover. Install the lower mounting bracket as shown in
Figure 7. Utilizing the bolts and lock nuts provided with
the bracket and placing the washers removed in proper
sequence, torque to 270-330 inch pounds. To determine
which end cover bolts to utilize to attach the bracket,
take into consideration the piping connections required
to install the AD-4
™
air dryer and use those that will best
position the unit for ease of installation.
2. A universal mounting plate (Pc. No. 248478) is available
to facilitate the mounting of the AD-4
™
air dryer. It is not
included in kits but can be obtained through an authorized
Bendix parts outlet.
3. Use 3/8" bolts (grade 5 min.) and washers (not furnished)
to mount the AD-4
™
air dryer to the vehicle. Torque to 25
ft. Ibs. (300 inch pounds).
CONNECTING THE AIR LINES
PURGE CONTROL LINE
1. Install a purge control air line having a minimum inside
diameter of 3/16 inches between the AD-4
™
air dryer
end cover control port and an unused unloader port on
the governor. The control line must be plumbed direct to
the governor and not in series with automatic drain valves,
lubrication systems, etc.
2. The control line should slope downward to the end cover
without forming potential water traps.
DISCHARGE LINE
General:
Refer to Appendix A, Table A for recommended discharge
line lengths and sizes for various vehicle applications and
vocations.
PURGE EXHAUST LINE
1. If it is necessary to direct AD-4
™
air dryer discharge
contaminants away from vehicle components a 1.5 inch
(38.1 mm) I.D. hose can be clamped on the AD-4
™
air
dryer exhaust cover.
WIRING THE HEATER/THERMOSTAT
1. Note the required voltage and wattage for the AD-4
™
air
dryer heater by checking the end cover as shown in
Figure 8.
2. Remove the rubber boot covering the single electrical
terminal of the standard AD-4
™
air dryer end cover. Install
a 16 gauge wire between the “on” position of the vehicle
ignition or engine “kill” switch and the heater/thermostat
electrical terminal. An 8-10 amp fuse is required in this
line regardless of voltage.
