Section IV. Maintenance procedures
General. Maintenance for this system consists of disassembling, repairing/replacing, and reassembling Items
listed in the repair parts listed In TM 55-1930-209-14&P-18. When performing maintenance, be sure to observe
precautions listed in manufacturers' manuals/instructions and the following
Always use new seals and gaskets, same as original, before reassembling components that have been
disassembled for repair. Carefully install so as not to damage during assembly.
When replacing gaskets, make sure mating surfaces are clean and free of old gasket material, adhesive, oil, or
grease. These precautions will ensure a leak-proof joint.
When replacing O-rings, make sure all surfaces are clean and free of dirt, grit or foreign material. Prior to
installation, apply a thin coat of silicone grease to O-ring for ease of assembly. Protect O-rings by applying tape
over threads, sharp corners and edges of components in which the O-ring will be placed.
Be sure electrical power is off and air pressure is zero before performing
maintenance on this system Open power panel 1 circuit breaker 3P5. Turn
compressor electric controller OFF. Bleed air pressure from receiver by opening
receiver drain cock. Bleed air pressure from lines by turning air station air valves
counterclockwise until they stop. Observe safety precautions listed In front of this
volume and those specified in manufacturers' manuals/instructions.
When replacing electrical components, follow proper procedures for soldering or crimping connections. Check all
grounding Make sure current carrying members are properly insulated to avoid short-circuiting Check for
abrasions and chafing of Insulation on wires and cables. Repair with tape or replace as necessary.
Air pressure regulators 1 and 2
4-5.1.1 Repair. Upon detection of leaks, pressure fluctuation or pressure creep, or for semiannual maintenance services,
perform these procedures:
a. Shut down air compressor system by following procedures In paragraph 3-8.2.
Redtag power panel 1 circuit breaker 3P5 indicating, "WARNING DO NOT ACTIVATE REPAIRS BEING MADE."
On air pressure regulator, unscrew bottom plug (or pressure gauge If installed in this manner) and remove bottom
plug O-ring, bottom spring and disc assembly. Inspect valve seat for damage or wear. See Figure 4-1 for
Identification of parts.
Inspect valve seat in head casting for foreign material or damage. Clean with soapy water, rinse, and dry with
Replace any damaged parts using repair kit (CAGEC 04049, Part No. 1586R) parts (bottom plug O-ring, bottom
spring, and/or disc assembly).
Assemble pressure regulator in sequence shown in Figure 4-1.
g. Start air compressor system by following procedures in paragraph 3-2.1 .
Check for proper operation If still malfunctioning, shut down air compressor system by following procedures in
paragraph 3-8.2 Then perform steps j through s i. If working properly, proceed to step r.
j Remove six screws attaching bonnet to head casting and remove bonnet.
Remove spring button, adjusting spring and relieving diaphragm. Figure 4-1 shows parts identification.
Inspect diaphragm and diaphragm seat In head casting for tears, wear, or foreign material