MCi Crusader II 1989 Maintenance Manual page 165

Date 1-1-89 .
Page · __
4-_3_s - -
MC-9 MAINTENANCE MANUAL
9
g=:
5 1 . Body
2. Stem
6
3.
Inlet Volve
o-,
4. Spring Seat
5. Spring
6. Strainer
7. Cop -
¼
NPT
8 . Button
2 9. Cotter Pin
INSPECTION
Figure 4 • 42 • Air Horn Valve. lower housing assembly protecting against excessive pressure
1. Inspect air horn supply valve and seat. If damaged, they within the housing. Refer to figure 4-44.
should be repaired or replaced. The desiccant sealing plate assembly is located midway in
2. Wash all air horn metal parts in cleaning solvent. the assembly and houses a replaceable ball-type single check
3. Carefully inspect the diaphragms to be sure they are not valve. Also located in the plate assembly is the purge orifice.
cracked. deteriorated. or distorted in any way. If ridges or The desiccant cartridge and the pleated paper oil filter are
cracks are found. the diaphragms must be replaced. removable and comprise a complete. serviceable unit
4. Inspect condition of the body. Be sure diaphragm seat in The desiccant, which is referred to as the "drying bed," is a
body is not chipped or damaged in any
way.
Check for cracks in drying substance that has the unique property of exposing a
the body and replace as necessary. tremendous surface area
in
proportion to its bulk. One pound of
5. Inspect the covers. Be sure diaphragm seat in cover is not desiccant beads has about two million square feet of adsorptive
chipped or damaged. Inspect the cover for cracks. area made up of a large number of microscopic cavities in each
6. Inspect the horn bells. If they are cracked or broken, they bead. Each desiccant bead adsorbs or collects moisture.
should be replaced. The desiccant is held in place by steel perforated plates and
7. Inspect the spring contacts. Replace if distorted or deter- filter cloths. The top plate is held in place by a spring and the
iorated. bottom plate rests on a shoulder approximately 1/a" (3.1 mm)
8. Check the spring; if broken. replace. from the bottom of the cartridge housing.
AD-2 AIR DRYE.R
The end cover assembly is retained by a lock ring, cap-
Prior to Unit 41089
screws and retainers and houses the purge valve and heater
assembly.
The AD-2 air dryer is installed atthefront of the front bogie in
the main air line between the compressor and the wet air tank.
See figure 4-43. The purpose of the air filter dryer is to remove
water and oil vapor from the air system, by means of condensa-
tion and a desiccant This provides longer component life and
helps prevent freeze-up. The system is self purging during the
unloading cycle of the air compressor.
The housing assembly consists of two cylindrical steel
stampings welded together. A safety valve is mounted in the
The heater and thermostat assembly prevent freeze-up in
the purge drain valve when the dryer is used in severe winter
conditions.
The 120 watt, 24 volt DC heater and thermostat assembly has
an operating range between 50°F - 85°F (10°C - 29°C).
NOTE: The heater and thermostat auem-
bly provided with the dryer has a 3/18" (4.7
mm) diameter threaded electrical terminal
protected by a boot. It I• nonHrvlceable.