Air Dryer - Peterbilt 348 2017 Operator's Manual

Twice a Year
•
Maintain the air compressor to
prevent excessive oil bypass.
See your maintenance manual for
details.
•
Replace worn seals in valves and
air motors as they are needed.
(03/17)

Air Dryer

The function of the air dryer is to collect
and remove air system contaminants in
solid, liquid and vapor form before they
enter the brake system. It provides
clean, dry air to the components of
the brake system, which increases
the life of the system and reduces
maintenance costs.
NOTE
Because no two vehicles operate
under identical conditions, mainte-
nance and maintenance intervals
will vary. Experience is a valuable
guide in determining the best main-
tenance interval for any one partic-
ular operation.
Every 900 operating hours or 25,000
miles (40,200 km) or every three (3)
months check for moisture in the air
brake system by opening air tanks,
Y53-6060-1C1
AIR SYSTEM
drain cocks, or valves and checking for
presence of water.
NOTE
A small amount of oil in the system
may be normal and should not, in it-
self, be considered a reason to re-
place the desiccant cartridge. Oil
stained desiccant can function ade-
quately.
A tablespoon of water found in the
air tank would point to the need for a
desiccant cartridge change. However,
the following conditions can also
cause water accumulation and should
be considered before replacing the
desiccant cartridge.
•
Air usage is exceptionally high
and not normal for a highway
vehicle. This may be due to
accessory air demands or some
unusual air requirement that
does not allow the compressor
to load and unload (compressing
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