BENDIX SD-08-2418 Manual page 9

If the Bendix AD-IS
® ®
not perform within the pressure ranges as described
above, recheck using gauges known to be accurate.
If the readings remain outside of the ranges outlined,
replace the AD-IS air dryer & reservoir system. NOTE:
There are no kits available for the servicing of the
pressure protection valves.
Do not attempt to adjust or service the pressure
protection valves – incorrect pressure protection valve
settings can result in the automatic application of the
vehicle spring brakes without prior warning (in the event
one of the supply circuits experiences rapid pressure
loss).
GENERAL
When rebuilding or replacing components of the air dryer
& reservoir, use only genuine Bendix
parts. For ease in servicing, the AD-IS air dryer & reservoir
have been designed so that maintenance kits can be
installed without removing the air dryer & reservoir from
the vehicle.
Always depressurize the air dryer and purge reservoir – and
all other reservoirs on the vehicle – to 0 psi before servicing
the air dryer.
If – after completing the routine operation and leakage
tests – it has been determined that one or more components
of the air dryer requires replacement or maintenance, refer
to the Maintenance Kit listing shown in this manual or the
Bendix Quick Reference Catalog for the appropriate kit(s).
®
The Quick Reference catalog (BW1114) can be ordered
and viewed on line at bendix.com.
Note: Kits are not available for the servicing of the pressure
protection valves (See Figure 5). Do not attempt to adjust
or service the pressure protection valves – these are not
service items.
TESTING THE BENDIX
& RESERVOIR SYSTEM
Before placing the vehicle into service, perform the
following tests:
1. Close all reservoir drain valves.
2. Build up system pressure to governor cut-out and note
that the Bendix AD-IS air dryer purges (with an audible
burst of air), followed immediately by air flowing out of
the purge valve. This purge time is related to the purge
volume as shown in Table 2.
air dryer & reservoir system does
brand replacement
®
AD-IS AIR DRYER
® ®
3. Apply and release the service brakes to reduce system
air pressure to governor cut-in. Note that the system
once again builds to full pressure and is followed by a
purge at the air dryer exhaust.
4. It is recommended that the total air system be tested for
leakage to ensure that the AD-IS air dryer & reservoir
system will not cycle excessively.
BRAKING SYSTEM PROTECTION
The Bendix AD-IS air dryer allows the system to maintain
one brake circuit, up to about 100 psi, even after a pressure
loss in the other brake circuit. This allows a vehicle to
be moved (in an emergency), but with reduced braking
capacity. Compare this to a conventional system, where a
loss of pressure in one service tank leaves the vehicle with
a limited number of reduced braking capacity applications
before the parking brakes automatically apply and stay on.
See Bendix publication BW5057 "Air Brake Handbook."
Bendix AD-IS Air
® ®
Dryer Governors Are
Non-adjustable
(feature a breather valve
in this port)
Figure 5 - Pressure Protection Valve Locations
WARNING
DO NOT ATTEMPT TO ADJUST OR
SERVICE THE PRESSURE PROTECTION
VALVES. INCORRECT PRESSURE
PROTECTION VALVE SETTINGS CAN
RESULT IN AUTOMATIC APPLICATION
OF VEHICLE SPRING BRAKES WITHOUT
PRIOR WARNING.
Pressure Protection
Valve Locations
9