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CHASSIS INFORMATION — 10
The air braking system on the motorhome
is equipped with a low air pressure warning
safety feature. Should a low air condition occur
while the vehicle is in operation, a warning
buzzer will sound and a dash warning light will
illuminate at approximately 60 to 65 psi (pounds
per square inch) to alert the operator.
Park & Emergency Brake System
The Park and Emergency Brake System
(Spring Brakes) applies to the rear drive
axle only. When the park brake is applied,
air is released from the rear brake chambers,
allowing the large spring in each rear brake
chamber to push the brake pads against the
rotor. The air system must be charged above
35 psi to allow the park brake to release.
Pushing down on the park brake handle charges
the rear brake chambers with air pressure,
overriding the emergency brake springs and
releasing the brakes. In the event of air loss
while the vehicle is under operation, the park
brake will automatically apply (this occurs at
approximately 30 psi), acting as an automatic
emergency brake system.
When preparing to depart, allow the air
system to achieve full air pressure as indicated
by the air gauge needles. Listen for the air
dryer to purge, indicating that the air dryer is
functioning. Look and listen for abnormalities.
Abnormal air pressure readings by either needle
of the air gauge alerts the operator to have the
air system checked to avoid an untimely failure.
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Should a failure occur in the air system,
preventing the air pressure from building, it may
become necessary to "cage" the spring brakes
(Section 2 Towing Procedures - Disabling
Parking Brake). This is an emergency procedure
only. Caging the rear air brake chambers
manually overrides the spring brakes and allows
the vehicle to move. This procedure does not
affect normal service braking.
NOTE:
When the park brake is released, the
Park illumination lamp will remain lit
until air system pressure is above 65 psi.
WARNING:
If the air tank is not depleted when
parked, it is possible to accidentally
release the parking brake. Traveling with
small children and/or pets may require
a small block to be fabricated to prevent
accidental release. The block should be
placed under the knob on the dash panel.
A wooden clothes pin, clasped at the base
of the shaft, will work.
Automatic Slack Adjuster
The braking system is equipped with automatic
slack adjusters. As brake lining wears, the slack
adjusters will automatically ratchet on the return
stroke as needed. This ratchet action will keep
the brake lining at proper adjustment. Automatic
slack adjusters and the connecting S-cam shaft
require periodic lubrication and inspection.
2 00 8 I MP E R I A L
WARNING:
DO NOT manually adjust the slack
adjusters. If any loss of braking
effectiveness or abnormal braking
indications are noticed, the brakes and
slack adjusters should be inspected by a
qualified brake technician.
NOTE:
Replacement parts should be of the
same original equipment size and type.
Mixing brake components may result
in unequal braking action. Brake
maintenance is not covered by the
manufacturer.
WARNING:
Brake lining may contain asbestos
material and should only be serviced
by qualified service technicians
who are trained in the appropriate
precautionary procedures.
Brake Systems - Backup
The motorhome air braking system is
equipped with backup safety systems and
warning alarms in the event of air system
failure. For example: should the air compressor
fail to charge the air system and low air
gauge readings go undetected, a low air
pressure warning buzzer will sound and a
low air pressure dash warning indicator light
will fl ash. These warning indicators occur
at approximately 65 psi. This will alert the
operator of an impending situation. If the
motorhome is allowed continued operation,
the pneumatic emergency spring brake relay
valve, installed in the air system, senses the low
air pressure condition and will release the air
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