9
FIGURE 6 - BENDIX
®
AD-IS
®
AIR DRYER AND RESERVOIR SYSTEM DELIVERY CHECK VALVE
GOVERNOR GASKET
(SPECIAL GASKET,
SEE ASSEMBLY NOTE 6)
GOVERNOR
(NON-ADJUSTABLE,
130 PSI CUT-OUT)
BOLTS
ADAPTER
LARGE
O-RING
SPRING
CHECK VALVE
BODY
SMALL
O-RING
ROADSIDE INSPECTION
In the event of a roadside inspection the system behavior
will be as follows: When the system is charged to
governor cut-out and then one reservoir drain valve is
opened, initially both reservoir gauges will fall; however,
the Bendix
®
AD-IS
®
air dryer primary and secondary
pressure protection valves will close at pressures above
70 psi, protecting the remaining brake circuit from further
loss of pressure.
TEMPORARY AIR DRYER AND RESERVOIR
SYSTEM BYPASS
To temporarily bypass the air dryer, follow these procedures:
Adhere to the General Safety Guidelines outlined
elsewhere in this document.
Make sure that all residual pressure has been released and
the air dryer purge reservoir has been drained to 0 psi,
then remove the air supply line from the compressor to the
inlet port (1/IN). Remove the safety valve from the Bendix
AD-IS air dryer (see Figure 1 for location). Note that a short
puff of trapped air may vent from the safety valve port when
removing the valve. Install a T-fi tting into the port. Using
any adapters necessary, reinstall the safety valve in one of
the branches of the T-fi tting. Using any adapters necessary,
install the air supply line into the remaining T-fi tting port.
After testing the T-fi tting for any air leakage—by using a
soap solution after charging to system cut-out pressure (a
1” bubble in 10 seconds is acceptable)—the vehicle may
be returned to temporary service.
Note: This is a temporary bypass of the air dryer. Full
repair of the unit must be carried out at the earliest
opportunity.
With the air dryer removed from the system,
contaminants will be entering the air brake system:
reservoirs will need to be manually drained daily until the
repairs are completed. At the end of each working day,
park the vehicle and slowly drain pressure through the
drain valves—leave open to the atmosphere—for several
hours, if possible. When repairs are carried out, be sure
to check that all reservoirs (including the air dryer purge
reservoir) are emptied of all contaminants.
If, after bypassing the air dryer and reservoir system, the
system pressure still does not build, use the following
procedure to remove, clean, and reinstall the delivery
check valve.
