2-19. ADJUSTING PLATFORM HEIGHT
If the semitrailer is loaded, DO NOT make any platform adjustments while
uncoupled or severe damage to equipment may result.
The suspension shut-off valve handle must be pulled outward to the ADJUST
position prior to operating any platform/gooseneck valve handles. The suspension
shut-off valve isolates the suspension and prevents operation. If the valve handle
is not properly positioned for intended operation, severe damage to equipment
b. Pull out handle of suspension shut-off valve (1) to ADJUST position (para. 2-6).
Ensure both streetside and curbside front bogie wheels are chocked. After the
parking brakes are released, the semitrailer may roll uncontrolled and cause injury
to personnel or damage to equipment may result.
The brakes on the semitrailer should be released when making platform
adjustments. If the parking brakes are not released, platform adjustments will be
much slower and harder to accomplish.
c. If semitrailer is coupled, release semitrailer parking brakes. If semitrailer is uncoupled and semitrailer air tanks
contain sufficient air, push in knob of brake release valve to release brakes (para. 2-8).
If semitrailer is coupled to a tractor, the gooseneck isolation valve handle must be
in the RUN position (handle pushed inward). If semitrailer is uncoupled and
gooseneck needs adjusting, verify that front support legs are lowered and
supporting the platform and all personnel are clear of gooseneck before operating
gooseneck isolation valve or injury to personnel may result.
d. If semitrailer is uncoupled and gooseneck needs to be raised, ensure handle of gooseneck isolation valve (2) is in
the ADJUST position, handle pulled outward. If semitrailer is coupled, ensure handle of gooseneck isolation valve
(2) is in the RUN position, handle pushed inward.