Monaco 2009 Knight, Owner'S Manual

Page: 211 / 260

20
2009
K
night
Chassis Information - 1
0
Actuating components inside of the valves
are oil dampened to reduce valve reaction to
momentary suspension bounce and rebound.
When a constant suspension change occurs,
such as a load change or weight transfer
through a sustained corner, the valve reacts by
adding or purging air from the air springs as
needed.
The air springs mount between the axle H-
frame assembly and the two main frame rails.
Air spring support plates mount to the main
frame and the H-frame. There is a specified
distance the air spring must maintain between
the mounting plates. Other than specified
distance between the plates will compromise
ride quality and handling, and affect shock
absorber travel, drive shaft angle, as well as
various other running gear components.
BRAkE SYSTEMS
Air Brakes
The air brake system on the motorhome
differs from a conventional automotive
hydraulic braking system and should be treated
differently. Proper maintenance and lubrication
are the keys to keeping the air brake system in
working order.
The air system supplies air to the foot brake,
or treadle valve. Pushing down on the treadle
valve supplies an air charge signal to a sealed
brake chamber that consists of a spring and air
bladder. The air charge signal pushes on the
bladder and extends a threaded rod connected
to the automatic slack adjuster. The slack
adjuster rotates the S-cam expanding the shoes
against the drum. Air disc brakes follow much
the same principle, with the exception of the
threaded rod directly activating calipers.
Consideration needs to be given to stopping
distances and air system pressures. The
motorhome requires longer stopping distances.
Each brake application uses air from the
air system, and engine speed is directly
proportional to how fast that air system is
replenished. Prepare for downhill grades. It
may be necessary to select a lower gear and/or
use the exhaust brake. Use individual short
brake applications down long hills, rather
than “riding” the brakes, to extend the life
of the brake lining. Avoid overheating the
brakes. Hot brakes have less stopping power.
When maneuvering the motorhome around
small areas, or backing into spaces, several
individual brake applications might be made.
Watch the air gauge. When preparing to back
into a space swing the motorhome so it is
aligned with the parking slot before backing
up.
The air braking system on the motorhome
is equipped with a low air pressure warning
system safety feature. Should a low air
condition arise 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 manually 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 function. 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.
Should a failure occur in the air system,
preventing the air pressure from building, it
may become necessary to “cage” the spring
brakes (
“cage” procedure in 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.