SECTION 12: BRAKE AND AIR SYSTEM
8
DOB 2490-2789 | X3-45 Commuter PA1605 Maintenance Manual (Final Version – Rev.2 April 2016)
Meritor Wabco Installing the Meritor
Wabco System Saver 1000, 1200 Se-
ries Air Dryers TP-92116
7.1 AIR
DRYER
REPLACEMENT
5. Apply parking brakes, set the ignition switch
to the OFF position.
WARNING
Relieve the air pressure in the air system prior
servicing any component in the air system.
Pressurized air can cause personal injury.
6. Purge the air dryer and wet air tank. To do
so, open the air system emergency air-fill
valve drain cock (Figure 3).
7. Unplug the air dryer electrical connector
(L350AA, port
II
) (Figure 8).
8. Unplug the air pressure sensor connector
(L350AB, port 21).
FIGURE 8: WABCO AIR DRYER CONNECTIONS
9. Disconnect the three following air lines:
Air supply from Haldex Consep
condenser-separator (#12 black textile
braid with two green stripes, port 1);
Air supply from emergency fill valve (1/4
green, port 1);
Air supply from front bumper fitting (1/2
brown, port 1).
10.
Disconnect the compressor governor
unloader control line (1/4 yellow, port 4).
11. Disconnect the delivery line to wet tank (3/4
green, port 21).
12. Unscrew and remove three bolts mounting
the air dryer to the bulkhead.
13. Remove and transfer the inlet (port 1) fittings
assembly as a single unit to the new air
dryer assembly. Install the fitting assembly
with an angle of 50° as shown on Figure 9.
NOTE
Use Loctite 567 Thread Sealant on all NPT
threads.
14. Remove and transfer the outlet (port 21)
fittings assembly (1 elbow + 1 tee) as a
single unit to the new air dryer assembly.
Install the fitting assembly with an angle of
45° as shown on Figure 9.
15.
Remove and transfer the compressor
governor unloader control line fitting to the
new air dryer assembly.
FIGURE 9: FITTINGS DIRECTION
16. Mount the new air dryer assembly similarly.
Torque mounting bolts to
22-30 lbf-ft
.
17. Connect air lines and electrical connectors
to new air dryer as previously installed
(Figure 8).
18. Close the air system emergency air-fill valve
drain cock (Figure 3).
7.1.1 Testing the installation
1. Close the drain cocks on all reservoirs.
2. Start the bus. Wait for the air system to
reach full operating pressure (122psi-
140psi).
3. If the air dryer exhausts air for 10-20
seconds after the governor cuts out, it is
working correctly.
4. Apply vehicle brakes several times until the
compressor cuts in.
5. If the air dryer exhausts air for 10-20
seconds after the compressor cuts out, it is
working correctly.
