operators_manual

To eject moisture from the air system
tanks, pull the line that is connected to the
moisture ejection valve. Continue pulling
until the air comes out free of water.
Daily
The supply and service air tanks, must be
drained on a daily basis. Operate air
devices daily to circulate lubricants within
the unit.
Periodically
Clean filter screens ahead of the valves by
removing the screens and soaking them in
solvent. Blow them dry with pressurized air
before reinstalling them.
• Maintain the air compressor to
prevent excessive oil bypass.
• Replace worn seals in valves and
air motors as they are needed.
Your authorized dealer carries
rebuild kits for most units.
How to Check for Air
System Leaks
Use these steps if the air gauges in the
dash or any warning lights turn on that
indicate that a air leak exists in the system.
Checking for air leaks should also be done
after any service or repair has been done
to the air system.
WARNING
Do not operate the vehicle if leakage
in the air system is detected. Conduct
the following procedure and contact an
authorized dealer (or any other proper-
ly equipped service center) if a leak is
detected. Failure to check the brakes
or follow these procedures could
cause a system failure, increasing the
risk of an accident and may result in
death, personal injury,equipment or
property damage.
1. Build up air pressure in the system
to the governor cutout point or until
120 psi (827 kPa) is reached.
2. Stop the engine and release the
service brakes.
3. Without applying the brake pedal,
observe the rate of air pressure
drop. This rate should not exceed
2.0 psi (14 kPa) per minute.
4. Start the engine and build up the
air pressure again.
5. Stop the engine, and apply the
brakes fully. Apply the brake pedal
and hold it down for five minutes.
The pressure drop should not
exceed 3.0 psi (21 kPa) per
minute.
6. If you detect excessive leakage (air
pressure loss greater than 3.0 psi
(21 kPa) after five minutes of brake
application), a leakage test should
be made at the air line connections
and at all air brake control units.
These tests should determine where air is
escaping.
MAINTENANCE - How to Check for Air System Leaks
212 Y53-6047-2HEN (03/18)
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