Preventive Maintenance; Sectional View - BENDIX AD-IP INTEGRAL PURGE AIR DRYER Manual

DESICCANT
BED
OIL
SEPARATOR
PURGE
ORIFICE
CONTROL
PORT
SUPPLY
PORT
TURBO
CUTOFF
VALVE
PURGE
VALVE
CARTRIDGE
Old Style End Cover -Vertical Delivery Check Valve
™
FIGURE 7 - AD-IP AIR DRYER SECTIONAL VIEW
connected to the engine turbocharger. The turbo cutoff valve
also removes the "puffing" of air out the open purge exhaust
when a naturally aspirated, single cylinder compressor,
equipped with an inlet check valve, is in use.
At the onset of the purge cycle, the downward travel of the
purge piston is stopped when the turbo cutoff valve (tapered
portion of purge piston) contacts its mating metal seat in
the purge valve housing. With the turbo cutoff valve seated
(closed position), air in the compressor discharge line and
™
AD-IP air dryer inlet port cannot enter the air dryer. In this
manner the turbo cutoff effectively maintains turbocharger
boost pressure to the engine.

PREVENTIVE MAINTENANCE

Important: Review the warranty policy before performing
any intrusive maintenance procedures. An extended warranty
may be voided if intrusive maintenance is performed during
this period. Note: It is acceptable for the purge valve to be
maintained as necessary, i.e., the installation of a purge
valve maintenance kit, without voiding the warranty.
Because no two vehicles operate under identical conditions,
maintenance and maintenance intervals will vary. Experience
is a valuable guide in determining the best maintenance
interval for any one particular operation.
PURGE
VOLUME
CHECK
VALVE
(BLACK)
DELIVERY
PORT
BOLT
DESICCANT
CARTRIDGE
CARTRIDGE
BOLT
CHECK VALVE
New Style End Cover - Horizontal Delivery Check Valve
Every 900 operating hours, or 25,000 miles or three (3)
months:
1. Check for moisture in the air brake system by opening
reservoirs, drain cocks, or drain valves and checking for
presence of water. If moisture is present, the desiccant
cartridge may require replacement; however, the following
conditions can also cause water accumulation and
should be considered before replacing the desiccant:
A. An outside air source has been used to charge the
system. This air does not pass through the drying
bed.
B. Air usage is exceptionally high and not normal for a
highway vehicle.
This may be due to accessory air demands or some
unusual air requirement that does not allow the com-
pressor to load and unload (compressing and
non-compressing cycle) in a normal fashion. Check
for high air system leakage. If the vehicle vocation
has changed it may be necessary to upgrade the
compressor size. Refer to Appendix A, Table A and
the column entitled Vehicle Vocation.
C. The air dryer has been installed in a system that
has been previously used without an air dryer. The
system will be saturated with moisture and several
weeks of operation may be required to dry it out.
O-RING
(WHITE)
SPRING
PIPE PLUG
DELIVERY
PORT
5