freightliner M2 Plus Maintenance Manual page 116

42
12.3 Fan 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 AD-IP air dryer exhaust.
12.4 Check for excessive leakage around the
head of the desiccant cartridge where it
contacts the end cover. With the
compressor in loaded mode (compressing
air), apply a soapy solution to these
areas, and observe that any leakage
does not exceed a 1-inch bubble in 1
second. If leakage exceeds this measure,
remove and re-install the desiccant
cartridge.
AD-9si and AD–IS
1. Park the vehicle on a level surface, apply the
parking brakes, and chock the tires.
2. Drain the air reservoirs.
3. Using a strap wrench or equivalent, loosen the
desiccant cartridge. Spin the cartridge off by
hand and discard it. See
1
10/07/2016
1. Desiccant Cartridge
2. Cartridge Sealing Ring
3. Threaded Base Post
Fig. 3, Desiccant Cartridge Replacement
4. On the new desiccant cartridge, lubricate the
sealing rings with silicone grease.
42/4
Fig. 3.
2
3
f421910
IMPORTANT: Only use the silicone grease
supplied with Bendix replacement kits.
5. Screw the desiccant cartridge onto the body by
hand until the seal makes contact with the body.
Rotate the cartridge clockwise about one full
turn. Tighten the cartridge firmly.
42–03 Governor D–2A Check
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.
Every 12 months, 100,000 miles (160 900 km), or
3600 operating hours, perform the operational test
below.
Operational Test
1. Start the vehicle engine, build air pressure in the
brake system, and check the pressure registered
by a dash or test gauge at the time the governor
cuts-out, stopping the compression of air by the
compressor. Cut-out pressure should be in
accordance with the pressure setting of the piece
number being used. Common cut-out pressures
are 125 to 135 psi (862 to 931 kPa). With the
engine still running, make a series of brake
applications to reduce the air pressure, and
observe at what pressure the governor cuts-in
the compressor. As in the case of cut-out
pressure, cut-in pressure should be in
accordance with the pressure setting of the piece
number being used. Cut-in pressure is 105 psi
(724 kPa).
NOTE: If the governor cover is marked
nonadjustable, and the adjusting stem has been
sheared off, this is a non-serviceable governor
and it must be replaced with a new or
remanufactured unit.
2. Never condemn or adjust the governor pressure
settings unless they're checked with an accurate
test gauge or a dash gauge that's registering
accurately. If the pressure settings of the D-2
governor are inaccurate or it's necessary that
they be changed, the adjustment procedure
follows.
Business Class M2 Plus Maintenance Manual, 02/10/2023
Brakes