Air Dryer
Climactic conditions affect performance
of desiccant or after-cooler type air dryers.
You must establish a maintenance
schedule for each specific operation.
The use of an air dryer on a vehicle does
not eliminate the need to drain the air
reservoirs periodically.
Inspect for moisture in the air system by
opening reservoirs, draincocks or valves
and checking for presence of water. The
presence of small amounts of water due
to condensation is normal and is not an
indication that the dryer is not functioning
properly.
Replace or rebuild the desiccant cartridge
when you determine that the desiccant is
contaminated and does not have adequate
water absorption capacity. The desiccant
change interval may vary. A general
recommendation is to replace the
desiccant every 12 months (yearly). If
experience has shown that extended or
shortened life has resulted for a particular
installation, then the yearly interval can be
increased or decreased accordingly.
Draining the Air Brake Reservoir
WARNING
Failure to drain air brake reservoirs
can result in a reduction or loss of
braking ability due to fluid
accumulation in the reservoir and/or
possible freeze-up during cold weather.
Completely drain all the air brake reservoirs
daily by opening the draincock at the ends
of the tanks. (Where accessible.
Pull-chains are used when the drains are
undercab or otherwise inaccessible.) Close
the draincock after draining. Manually drain
any air tanks equipped with automatic
moisture ejector valves, as required, to
maintain a dry air system. Contact an
authorized dealer if you are unsure of the
air reservoir locations or the draining
procedure.
Hydraulic Brakes
Establish a regular schedule for periodic
cleaning, lubrication and adjustment
inspection based on vehicle use. Exact
maintenance intervals are difficult to
predetermine due to vehicle applications
and operating conditions. If you are
uncertain of the proper schedule for your
vehicle, contact an authorized dealer.
Regular inspections should include:
•
Checking the brake lining (every service
interval). Establish inspection intervals
that provide for lining replacement
before damage to the disc occurs.
Excessive lining wear may expose the
backing plate to the disc causing
scoring of the disc faces. A qualified
technician should perform this
220
F650750 (TBC), enUSA, First Printing
Maintenance