Installation; Shock Absorbers - PREVOST H3-41 Maintenance Manual

a) Jack vehicle until the tire clears the
ground, and place safety supports
underneath body.
CAUTION
Only the recommended jacking points must be
used as outlined in Section 18, "Body".
b) Support the axle with a suitable
hydraulic floor
recommended jacking points. Make
sure that the measurement between
the air spring mounting plates is
greater than the normal clearance
(normal ride height).
c) Remove wheel.
2. Exhaust compressed air from accessory air
tank by opening drain cock under reservoir.
3. Disconnect the height control valve link and
pull down the control arm to ensure all air is
exhausted from air springs.
NOTE
While performing this step, do not change the
height control valve control arm adjustment.
4. Disconnect air line from air spring, remove
elbow (if applicable), and cover both the line
end and fitting to prevent the entry of foreign
matter.
5. Unscrew the two air spring lower mounting
nuts.
6. Rotate the air spring clockwise (Figure 3) to
free the upper
mounting plate.
7. Remove the air springs.
jack at the
attachments from the
SECTION 16 : SUSPENSION
FIGURE 3: AIR SPRING UPPER MOUNTING PLATE
3.1.3

Installation

1. Compress air spring as necessary and
position air spring between both the lower
and upper mounting plates.
2. Align the upper attachments with holes in the
mounting
counterclockwise.
3. Thread the lower nuts a few turns.
NOTE
To facilitate air spring installation, compress it
manually then put a piece of tape over the air
line threaded fitting. This prevents air from
getting back into the air spring and keeps it
compressed, thus enabling to place the air
spring in between the mounting plates and
greatly easing installation.
4. Tighten and torque the lower stud nuts
according to Torque Table under heading
Torque Specifications.
5. Install elbow (if applicable), then connect air
line.
6. Connect the height control valve link.
7. Build up air pressure in system.
NOTE
To accelerate this operation, air reservoirs can
be filled from an exterior air supply connected
to the accessory tank fill valve or to the
emergency fill valve.
7. Check operation of bellows and with the
primary air system at normal operating
pressure (122 - 140 psi (841 - 965 kPa)),
coat the air line connections and air spring
mounting areas with a water and soap
solution. Bubbles will indicate an air leak,
and none is permissible. Repair or replace
defective parts.
8. Reinstall wheel.
9. Remove the hydraulic floor jack from under
the axle, then lower vehicle to ground.
3.2

SHOCK ABSORBERS

Double-action, telescoping-type shock absorbers
ensure a smooth ride and enhance vehicle
PA1621 Maintenance Manual All Series | January 2017
plate. Rotate air spring
15