Monaco SIGNATURE 2001 series, Руководство пользователя

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When operating a vehicle equipped with air brakes, considerations need to be
given to stopping distances and air system pressures. The heavier the vehicle, the
greater the kinetic energy. The motorhome requires longer stopping distances.
Each brake application uses air from the air system. Give attention to the air
gauge as well as the surroundings. Engine speed is directly proportional to how
fast the air system is replenished. Prepare for downhill grades. Grades are general-
ly posted in percentages. It may be necessary to select a lower gear. Make use of
the engine or exhaust brake. When making brake applications, use individual short
applications down long hills rather than “riding” the brakes. This will extend the
life of the brake linings. Avoid overheating the brakes. Hot brakes have less stop-
ping power. When maneuvering the motorhome around in small areas or backing
into spaces, several individual brake applications might be made. Watch the air
gauge. Plan ahead when parking to make it easier on yourself. 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 several safety fea-
tures unlike that of automotive hydraulic braking systems. One safety feature is a
low air pressure warning system.Should a low air condition arise while the vehicle
is under operation, a warning buzzer will sound and a dash warning light will illu-
minate alerting the operator of the situation. This warning occurs at approximately
60-65 psi (pounds per square inch).
A simple mechanical explanation of what occurs when a brake application is
made is as follows: The air system supplies air to the foot brake, this is called a
treadle valve. Pushing down on the treadle valve supplies an air charge signal to a
brake chamber. This sealed chamber consists of a spring and air bladder. The air
charge signal pushes on the bladder which 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 principal, with the excep-
tion of the S-cams.
The park and emergency brake systems are combined and apply to the rear
drive axle only. These are called spring brakes. 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 against the automatic slack adjuster. This rotates
the S-cam applying the brake shoes against the drum. The air system must be
charged so the park brake will remain released. Pushing down on the park brake
handle charges the rear brake chambers with air pressure, overriding the emer-
gency 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.
This is indicated by the air gauge needles. Listen for the air dryer to purge, indi-
cating full air pressure has been obtained and air dryer is functioning. Look and
Chassis Information
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S I G N A T U R E 1 0 • 2 6 8
BRAKE -
PARK &
EMERGENCY
SYSTEMS