Blue Bird M380 2003, Руководство пользователя

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M380 Owner’s Manual_______________________Interior and Exterior Systems Operation – Air Pressure System – 4-15
Rev. “F” 4-15-1
4-15 Air Pressure System___
_____________________________
4-15.1 Description and Operation
An engine-driven compressor supplies the air pressure system on your motor home. It provides
pneumatic power for brakes, suspension, and numerous accessories. This complex, but efficient
system is not intended to be totally leak free. After overnight parking, you may notice a significant loss
of pressure on the air pressure front/rear gauge, or in systems connected to auxiliary air. This
condition is normal, and in fact, our air leakage tolerance is tighter than most manufacturers within the
heavy-duty equipment industry. Once the engine is running, the engine-driven compressor will quickly
build up the system to the correct pressure.
4-15.1.1 Air Brakes
Your motor home is equipped with dual service air brake systems for front and rear, with integral
fail/safe operation; and manual/automatic rear spring (parking) brakes. The service brakes are
completely independent systems, each including a reservoir and separate distribution lines and
valves. The reservoirs are pressurized from a single compressor. Both service brake systems are
brought into operation each time the brake treadle is depressed to slow or stop the motor home.
Reservoir pressure for each service brake system is monitored by a respective pressure gauge on
the front panel; system failure(s) are indicated by low-pressure readings, illumination of the Low Air
failure lamp and sounding of buzzer.
4-15.1.2 Operation
When the motor home is parked, and the engine off, the rear spring brake will normally be set by
operating the parking brake. The spring brakes cannot be fully released until the air pressure is above
65 psi. These brakes are in the released position when the control is pushed in. In the event that
there is a loss of air pressure, the spring brakes will set automatically at the brake-applied position,
and will not release until the air reserve has again built up to required value. Consequently, there will
be a normal delay, after the motor home is first started, while the compressor builds up pressure
before the brakes can be released and the motor home driven. When the brake treadle is depressed
to slow or stop the motor home, reservoir air is applied simultaneously to both front and rear service
brakes to effect the braking action. The spring brakes are held in a released position by the air
pressure supplied from the associated reservoir tank.
CAUTION: Do not attempt to drive the motor home until system pressure is above 90 psi.
4-15.1.3 Brake Failures
To compensate for normal lining wear, each brake system is individually self-adjusting.
Fail/safe features provide protection against brake system failures. If the front brakes fail, operating
the brake treadle still activates the rear service brakes to provide stopping capability.
If a failure occurs in the rear, the front service brakes and rear spring brakes provide braking action.
In the unlikely event of a failure where both service-braking systems are disabled, the rear spring
brakes will apply automatically and bring the vehicle to a stop. As a safety factory, the motor home
should not be moved until any type of brake failure is corrected.
NOTE: With the front brake system service reservoir fully charged, enough air pressure is
available to provide for four full releases of the rear spring brakes. This will allow the motor
home to be brought to a safe position until repairs can be accomplished.