Delivery Check Valve Cleaning Procedure - BENDIX AD-IS AIR DRYER Manual

FIGURE 7 - AD-IS ® AIR DRYER AND RESERVOIR SYSTEM DELIVERY CHECK VALVE
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, and
full repair of the unit must be carried out at the earliest
opportunity. With the air dryer and reservoir system
removed from the system, contaminants will be entering
the air system: reservoirs will need to be manually drained
daily until the repairs are completed. At end of each working
day, park 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.

DELIVERY CHECK VALVE CLEANING PROCEDURE

(Note: This is only required if system pressure does not
build after temporary bypass is completed.)
SMALL
O-RING
CHECK VALVE
BODY
SPRING
GOVERNOR GASKET
(SPECIAL GASKET,
SEE NOTE 6)
LARGE
O-RING
ADAPTER
See Figure 7 throughout this procedure. Depressurize the
air brake system following the general safety precautions
outlined elsewhere in this document. Also, always
depressurize the air dryer purge reservoir before servicing
the air dryer.
This procedure does not require removal of the AD-IS
dryer and reservoir system from the vehicle.
1. Remove the line from the governor and mark for easy
reinstallation.
2. Remove the bolts attaching the governor to the AD-IS
air dryer and reservoir system and retain for reassembly.
3. Remove the governor from the air dryer. Be aware that a
short puff of trapped air may vent when the governor is
removed. Retain the governor gasket for reassembly if
a new governor gasket is not available. Remove and
retain the o-ring from the adapter.
4. The spring/delivery check valve can now be removed.
5. Remove and retain the o-ring from check valve body.
GOVERNOR
(NON-ADJUSTABLE,
130 PSI CUT-OUT)
BOLTS
®
air
®
9