Monaco Executive 2005 - Height Control Valves

Section 10 --- Chassis Information
The Executive 2005
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HEIGHT CONTROL VALVES
Height Control Valves (HCV) inflate or deflate air springs to maintain proper suspension height
throughout the load range. Two Height Control Valves are installed at the rear drive axle to control rear
suspension height and left or right tilt of the motorhome. A separate HCV is installed to control
front suspension height. The three HCVs mount to the main frame of the motorhome, above the
axles, with a linkage rod connecting the valve to the axle.
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.
Should it become necessary to check the suspension ride height, start with the motorhome on a flat
level surface. The air system must be fully charged with the suspension normalized at ride height.
Specified distances may vary plus or minus ¼". Small offset adjustments to the rear valves may be
necessary to compensate for slight tilt. Example: Adjusting the curbside rear height control valve up
will pivot the roadside front corner down.
NOTE:
Drive shaft angle is affected by the suspension ride height. Improper drive shaft
angle can damage suspension or shorten the life of universal joints. Shock
absorbers and air springs are in travel centers at proper ride height. The ignition
must be on for the suspension to operate when equipped with HWH air leveling.